delivered the opinion of the Court. Eldridge, Cole and Davidson, JJ., dissent. Cole, J., filed a dissenting opinion at page 610 infra, in which Eldridge and Davidson, JJ., join.
In the criminal cause now before us, petitioner Calvin Watkins challenges the denial of his pretrial motion to suppress evidence obtained as a result of police activity which he asserts violated his right under the fourth amendment to the United States Constitution to be secure from unreasonable searches and seizures. Since we conclude that the complained of police conduct was not an impermissible intrusion into the petitioner’s personal security, we shall affirm the judgment of the Court of Special Appeals upholding his conviction for the illegal possession of a controlled dangerous substance.
The pertinent facts, agreed upon by the parties, can be *599succinctly stated. On February 12, 1978, at approximately 4:40 p.m., Police Officer John McEntee received an official radio transmission directing him to go to the 2100 block of Barclay Street in Baltimore City to assist an unidentified foot patrolman who was "in pursuit of two suspects reported to be armed . ...” 1 As Officer McEntee proceeded to that location in his marked cruiser, he overheard another transmission from the policeman on foot reporting that he had lost sight of the two suspects in the vicinity of the intersection of 21st and Barclay Streets. At the time of this second broadcast Officer McEntee, being within one block of that intersection, slowed his cruiser and observed 30 to 50 people throughout the 2000 block of Barclay, among whom were the petitioner and an unidentified person standing with him. As the police car approached, the petitioner’s companion yelled "run, police” and Watkins in response did flee by running into and through an alley. Officer McEntee immediately alighted from his vehicle and while calling out several times for the runner to stop, gave chase for a distance of some three blocks where, upon overtaking petitioner, the officer attempted to grab him from behind. At that point, Watkins turned and struck Officer McEntee in the mouth with the back of his hand, and the struggle that followed culminated with the subduing of the petitioner in a prone position on the ground. While in that posture, when Watkins attempted to reach for his right lower leg, Officer McEntee patted the exterior of the sock area and identified the soft, pliable object within it not to be a weapon. Petitioner was then placed under arrest for assaulting the officer and the more intensive search which followed produced from his sock a brown paper bag containing 73 glassine packets of what was later determined to be heroin.
As it turned out, Mr. Watkins was not one of the armed suspects who had evaded the foot patrolman. He was, however, tried, convicted and sentenced in the Criminal Court of Baltimore (Arabian, J.) for the illegal possession of heroin in *600sufficient quantity to indicate an intent to distribute that drug. The conviction was obtained only after a pretrial motion to suppress and exclude the heroin was denied, a ruling Watkins claimed on his appeal to the Court of Special Appeals constituted reversible error. That court, in an opinion written by Judge Liss, after determining that 'Ttjhese facts, as articulated by the police officer, were sufficient to raise a rational inference that the appellant may have been 'connected with criminal activity’ ”, concluded "that there was legal justification for the [Terry2] stop,” and affirmed his conviction and sentence. Watkins v. State, 42 Md. App. 442, 446, 400 A.2d 1143, 1146 (1979). We granted certiorari.
In urging that this Court reverse the judgment, the petitioner advances two reasons why the heroin was impermissibly seized, either of which, he asserts, would dictate that it could not be used as evidence against him. First, Watkins argues that Officer McEntee did not possess sufficient articulable facts which authorized the investigatory stop of the petitioner. And, second, he contends that even assuming that the officer had the requisite predicate for detaining Watkins, it is unreasonable under the fourth amendment to the United States Constitution to use physical force to effectuate the stop. Petitioner rationalizes that if either of these contentions is true, then his assault of the officer was justified,3 and his arrest for this crime was invalid, which in turn makes the article seized inadmissible in evidence since it was "fruit of the poisonous tree.” E.g., Wong Sun v. United States, 371 U.S. 471, 83 S. Ct. 407, 9 L. Ed. 2d 441 (1963).
We begin our analysis of the contentions raised by the petitioner with an examination of the principles established *601by the Supreme Court of the United States in the landmark case of Terry v. Ohio, 392 U. S. 1, 88 S. Ct. 1868, 20 L. Ed. 2d 889 (1968), which articulates the bedrock constitutional law largely determinative of the issues in this case.4 In Anderson v. State, 282 Md. 701, 387 A.2d 281 (1978), this Court summarized the applicable law announced by the Supreme Court in that case:
Terry dealt with the very narrow question of whether it is always unreasonable for a policeman to seize a person and subject him to a limited search for weapons when there is no probable cause to arrest him. Answering that question in the negative, the Court preliminarily rejected the notion that such investigatory detentions were not governed by the fourth amendment to the Federal Constitution. The Court observed that "whenever a police officer accosts an individual and restrains his freedom to walk away, he has 'seized’ that person” and that exploration of the outer surfaces of a person’s clothing is a "serious intrusion upon the sanctity of the person . . . and . . . not to be undertaken lightly.” The central inquiry is "the reasonableness in all the circumstances of the particular governmental invasion of a citizen’s personal security.” In determining whether the intrusion was justified at its inception, "the police officer must be able to point to specific and articulable facts which, taken together with rational inferences from those facts, reasonably warrant that intrusion.” The reasonableness of an intrusion is to be assessed against an objective standard — whether "the facts available to the officer at the moment of the seizure or the search 'warrant a *602man of reasonable caution in the belief that the action taken was appropriate.” [Anderson v. State, supra at 704-5, 387 A.2d at 283 (citations omitted).]
Though the Terry court did not specifically rule on the constitutional propriety of an investigative seizure, Terry v. Ohio, supra, 392 U.S. at 19 n. 16, but see id. at 32-33 (J. Harlan’s concurring opinion), decisions subsequent to Terry have left no doubt as to the constitutionality of such detentions, given proper circumstances. See Brown v. Texas, 443 U.S. 47, 50, 99 S. Ct. 2637, 61 L. Ed. 2d 357 (1979); United States v. Brignoni-Ponce, 422 U.S. 873, 878, 45 L. Ed. 2d 607, 95 S. Ct. 2574 (1975). "[T]he real thrust of Terry is directed at instances in which there is reasonable suspicion that someone is about to commit or has just committed a crime.” Anderson v. State, supra, 282 Md. at 706, 387 A.2d at 284. Thus, it is the manifest need for "necessarily swift action predicated upon the on-the-spot observations of the officer on the beat,” Terry v. Ohio, supra, 392 U.S. at 20, reasonably creating in the mind of the officer "some quantum of individualized suspicion,” United States v. Martinez-Fuerte, 428 U.S. 543, 560, 96 S. Ct. 3074, 49 L. Ed. 2d 1116 (1976); Delaware v. Prouse, 440 U.S. 648, 99 S. Ct. 1391, 59 L. Ed. 2d 660 (1979), that must be balanced against "the individual’s right to personal security free from arbitrary interference by law officers.” United States v. Brignoni-Ponce, supra, 422 U.S. at 878. See Brown v. Texas, supra, 443 U.S. at 50-51; Delaware v. Prouse, supra, 440 U.S. at 654-55.
Neither the Terry opinion, nor the Supreme Court decisions since that case, spell out with any precision the factors to be analyzed in determining whether the police officer had knowledge of specific and articulable facts justificatory of the detention of an individual on less than probable cause. The federal and state courts that have applied Terry, however, have commonly looked to several criteria in attempting to resolve whether the police officer had the requisite reasonable suspicion. This Court, for instance, in Anderson v. State, supra, 282 Md. at 707 n. 5, 387 A.2d at 285 n. 5, concluded that the character of the *603area, the temporal and spacial proximity of the stop to the situs of the crime, and the appearance and conduct of the suspect were relevant in adjudging reasonable suspicion. Similarly, in United States v. Wright, 565 F.2d 486 (8th Cir. 1977), cert. denied, 435 U.S. 974 (1978), a case factually akin to the one at bar, the court relied on the following circumstances in determining that the police conduct was valid: a radio dispatch reporting that a robbery had just been committed, the proximity of the suspect to the reported crime, and the suspicious conduct of the defendant upon awareness of the police presence. Id. at 489. Accord, Franklin v. United States, 382 A.2d 20, 22 (D.C. 1978), cert. denied, 440 U.S. 948 (1979); Project, Eighth Annual Review of Criminal Procedure: United States Supreme Court and Courts of Appeals 1977-78, 67 Geo. L.J. 317, 354-55 (1978); Note, Terry Revisited: Critical Update on Recent Stop-And-Frisk Developments, 1977 Wis. L. Rev. 877, 886 (the six variables most often identified are appearance, conduct, criminal record, environment, police purpose, and source of information).
Of the factors listed, the conduct of a defendant usually plays a key role in evaluating the propriety of a Terry stop since, as with petitioner’s flight in the case now before us, such conduct is what frequently focuses an officer’s attention on a particular suspect. Accordingly, we now mention the influence which flight has had in other decisions on the question of whether a Terry stop is authorized. In Peters v. New York, 392 U.S. 40, 88 S. Ct. 1889, 20 L. Ed. 2d 917 (1968), a companion case to Terry, the Supreme Court stated that deliberately furtive actions and flight at the nearing of police are strong indicia of mens rea. Id. at 66.While there are a minimal number of cases which hold that flight, without more, authorizes a Terry stop, see, e.g., People v. Waits, 580 P.2d 391, 393 (Colo. 1978) (enbanc) (abrupt evasive maneuver upon confronting police car alone sufficient to raise reasonable suspicion of criminal activity), the vast majority of decisions indicate disagreement. These latter rulings accord great weight to a suspect’s flight from police, but require that this conduct be corroborated by other *604suspicious circumstances before finding that there were reasonable grounds for the stop. See, e.g., United States v. Jones, 619 F.2d 494, 498 (5th Cir. 1980); United States v. Embry, 546 F.2d 552 (3d Cir. 1976), cert. denied, 430 U.S. 948 (1977) ; United States v. Vasquez, 534 F.2d 1142 (5th Cir. 1976), cert. denied, 429 U.S. 962 (1976); U.S. ex rel. Richardson v. Rundle, 461 F.2d 860 (3d Cir. 1972), cert. denied, 410 U.S. 911 (1973); Franklin v. United States, supra; Luker v. State, 358 So. 2d 504 (Ala. Cr. App. 1978); Commonwealth v. Battle, 365 Mass. 472, 313 N.E.2d 554 (1974); People v. Tebedo, 81 Mich. App. 535, 265 N.W.2d 406 (1978) ; Commonwealth v. Jeffries, 454 Pa. 320, 311 A.2d 914 (1973); cf. Braxton v. State, 234 Md. 1, 197 A.2d 841 (1964) (flight as it pertains to the existence of probable cause to arrest). As we agree with the majority of courts that view the unequivocal flight of a suspect upon seeing police as not alone necessarily indicative of criminal activity, we now examine the record here to determine if there are corroborating circumstances sufficient to create the reasonable suspicion necessary for the stop of petitioner.
Facts of which Officer McEntee had specific knowledge by either police radio or personal perception at the time he attempted to stop the petitioner were: a fellow police officer was pursuing two suspects reported to be armed; the suspects had eluded the foot patrolman just a few moments before Officer McEntee entered the city block in which they had last been seen; upon entering the block the officer heard the petitioner’s companion yell "run, police,” and observed Watkins run into an alley; and that in response to several calls to halt, the petitioner continued to attempt to evade the officer. We conclude that the totality of these factors, occurring as they did within a minimal time and space stricture, could well create in the mind of a cautious police officer a reasonable suspicion that criminal activity was afoot; consequently the investigatory stop of the petitioner was warranted under the Terry decision.5 We are guided in this *605determination by the complexity of "the rapidly unfolding and often dangerous situations on city streets [where] the police are in need of an escalating set of flexible responses, graduated in relation to the amount of information they possess.” Terry v. Ohio, supra, 392 U.S. at 10. "The Fourth Amendment does not require a policeman who lacks the precise level of information necessary for probable cause to arrest to simply shrug his shoulders and allow a crime to occur or a criminal to escape.” Adams v. Williams, 407 U.S. 143, 145, 92 S. Ct. 1921, 32 L. Ed. 2d 612 (1972). In our view, the situation that confronted Officer McEntee was of the genre specifically addressed by the Supreme Court in Terry, necessitating the "swift action” contemplated and approved by that decision. Accord, Anderson v. State, supra, 282 Md. at 705-06, 387 A.2d at 284. In the words of the drafters of the Model Code of Pre-Arraignment Procedure:
]W|here a crime may have been committed and a suspect or important witness is about to disappear, it seems irrational to deprive the officer of the opportunity to "freeze” the situation for a short time, so that he may make inquiry and arrive at a considered judgment about further action to be taken. To deny the police such a power would be to pay a high price in effective policing and in the police’s respect for the good sense of the rules that govern them. |ALI, A Model Code of Pre-Arraignment Procedure § 110.2, at 272 (Commentary 1975).]
The petitioner argues, nevertheless, that when evidence is challenged on fourth amendment grounds at a suppression hearing, the burden is on the State to establish the sources and reliability of the information upon which the seizing officer acted, including, as in this case, police radio *606broadcasts. This argument implicitly assumes that the rules governing the reliability of sources of information developed by the Supreme Court under the probable cause requirement of the warrant clause of the fourth amendment apply with the same force and effect to the mere reasonable suspicion standard required to effectuate the less restrictive intrusion of a Terry stop.6 Petitioner’s reasoning, however, ignores the fact that in Terry itself, the Court was very careful not to base its ruling on the warrant clause contained in the fourth amendment, but on that amendment’s more flexible reasonableness clause. See Terry v. Ohio, supra, 392 U.S. at 20. Moreover, we believe the Supreme Court, in its subsequent decision of Adams v. Williams, supra, has approved a lesser showing of reliability of the sources of information for investigatory stops and protective frisks than is required for arrests, and other types of authorized searches and seizures. In Adams a police officer, acting on an informant’s tip that a man seated in a nearby car had narcotics in his possession and a gun at his waist, approached the man and grabbed the gun from the suspect. Though there was no showing of the informant’s reliability as would seemingly be required by Spinelli v. United States, 393 U.S. 410, 89 S. Ct. 584, 21 L. Ed. 2d 637 (1969) and Aguilar v. Texas, 378 U.S. 108, 84 S. Ct. 1509, 12 L. Ed. 2d 723 (1964), the Supreme Court stated: "Thus, while [our] decisions indicate that this informant’s unverified tip may have been insufficient for a narcotics arrest or search warrant, the information carried enough indicia of reliability to justify the officer’s forcible stop of Williams.” Adams v. Williams, supra, 407 U.S. at 147 (citations omitted). Therefore, it would seem that "[r]easonable suspicion 'involves a significantly lower degree of objective evidentiary justification than does probable cause to arrest.’ ” State in Interest of H.B., 75 N.J. 243, 381 A.2d 759, *607763 (1977) (quoting from Survey of the 1973 Supreme Court Term, 27 Rutgers L. Rev. 465, 579 (1974). See, e.g., United States v. Zapata, 535 F.2d 358, 359 (7th Cir. 1976) (per curiam); United States ex rel. Mungo v. LaVallee, 522 F.2d 211, 214 (2d Cir. 1975), vacated on other grounds, 428 U.S. 907 (1976); United States v. Hernandez, 486 F.2d 614, 616-17 (7th Cir.) (per curiam), cert. denied, 415 U.S. 959 (1973); Franklin v. State, 143 Ga. App. 3, 237 S.E.2d 425, 426 (1977), cert. denied, 435 U.S. 950 (1978); State v. Ogata, 58 Ha. 514, 572 P.2d 1222, 1224 (1977); State v. Jernigan, 377 So. 2d 1222, 1224-25 (La. 1979); State v. Lange, 255 N.W.2d 59, 62-63 (N.D. 1977). But see United States v. Robinson, 536 F.2d 1298, 1299 (9th Cir. 1976); State v. Benson, 198 Nebr. 14, 251 N.W.2d 659, 661 (1977) (per curiam).
In our view, in the present case there are at least two factors leading to the conclusion that there existed ample "indicia of reliability” to justify the stop of the petitioner. First, there is the corroboration of the transmission inherent in the location where Watkins was initially observed and his subsequent flight when the police approached. See United States v. Zapata, supra; Green v. State, 348 So. 2d 428 (Miss. 1977); cf. Draper v. United States, 358 U.S. 307, 79 S. Ct. 329, 3 L. Ed. 2d 327 (1959). The second, and more weighty consideration, is manifest from the nature of the broadcast itself; the police transmission did not purport to convey merely a vague suspicion of criminal activity, but significantly reported that a foot patrolman was at that moment in hot pursuit of two armed suspects. The inference to be drawn from these transmissions, that the foot patrolman in pursuit had actual knowledge of criminal activity, could reasonably create in the mind of Officer McEntee a high level of suspicion that a crime had just occurred. Absent an indication that the police have manufactured the broadcast to circumvent the requirements of the fourth amendment, which we do not find in this record, we believe that the composition of this transmission supplies its own "indicia of reliability.” It is our view, that for purposes of investigative stops and protective searches, the flexibility inherent in the reasonableness clause of the *608fourth amendment requires that no arbitrary rule concerning proof of the basis of informational sources be applied to police communications. The reasonableness of a police officer’s actions must necessarily be judged, in part, by the content and nature of the transmission upon which he relies. We are not alone in this conclusion as is demonstrated by the opinion of the New York Court of Appeals in People v. DeBour, 40 N.Y.2d 210, 386 N.Y.S.2d 375, 352 N.E.2d 562 (1976), where it is stated:
'There is a difference of significant degree between a report only that a person has a gun in his possession and another report that a person not only has a gun but that he has just used it for the commission of a crime.’ Of course, where the report indicates that the person has used the weapon to menace or threaten or will use the weapon if stopped for questioning . . . then the personal and public safety may well mandate a more intensive police intrusion, [id. at 573 (quoting from People v. Green, 35 N.Y.2d 193, 360 N.Y.S.2d 243, 318 N.E.2d 464, 465 (1974). See also People v. Taggert, 20 N.Y.2d 335, 229 N.E.2d 581, 586 (1967); State v. Lesnick, 84 Wash. 2d 940, 530 P.2d 243, 246 (1975) (en banc)).]
Here, we have no doubt that Officer McEntee was entitled to rely on the inference, certainly reasonable under the circumstances, that the foot patrolman had direct knowledge of illegal activity on the part of the two armed suspects that he was attempting to capture. Consequently, we conclude that there existed sufficient indicia of reliability of the broadcast to justify Officer McEntee’s reliance on the information obtained from it, and that the police transmission, combined with the sequence of events which took place in his presence when he entered the 2000 block of Barclay Street, created the predicate justification for the stop of the petitioner.
The final argument advanced by petitioner in his attempt to vitiate his conviction is that the use of physical force to *609effectuate an investigatory stop is impermissible under the fourth amendment. We believe this contention neither states the prevailing constitutional law nor recognizes the practical reality and requirements of this type of police investigation. To embrace a rule such as that advocated by the petitioner would unnecessarily undermine the vitality of police investigation in the field, recognized and approved as a necessary ingredient of police practice in Terry. The petitioner, in light of the teachings of Terry, not unsurprisingly anticipates this conclusion and rejoins with a three-point analysis. He points out: 1) the majority of suspects submit to police questioning when approached on the street, 2) the fact that a person refuses to stop may provide the additional inference necessary to obtain probable cause to arrest the suspect, and 3) where probable cause to arrest does not exist, then the police officer "simply has insufficient information to justify an intrusion as serious as a physical seizure.” Even if we assume that the vast majority of suspects voluntarily submit to police questioning, see Pitcher, The Law and Practice of Field Interrogation, 58 J. Grim. L.C. & P.S. 465 (1965), it simply does not follow that the use of force to stop the few who do not submit is constitutionally impermissible. Furthermore, were the rule such that it permitted suspects to ignore a request to stop, we seriously doubt that the exercise of the consequent right to walk away would add much to the probable cause determination. More fundamentally, however, we believe the petitioner misconceives the nature of Terry and its progeny because a Terry stop is a forcible detention — a seizure of the person under the fourth amendment. Terry v. Ohio, supra, 392 U.S. at 16-19; see Adams v. Williams, supra, 407 U.S. at 146. Although it is not as serious an intrusion into the personal security of the suspect as an arrest, "whenever a police officer accosts an individual and restrains his freedom to walk away, he has 'seized’ that person.” Terry v. Ohio, supra, 392 U.S. at 16 (emphasis added). Moreover, the Supreme Court in Terry-noted the distinction between a seizure of the person and actions of a police officer that do not call into play the fourth *610amendment: "Obviously, not all personal intercourse between policemen and citizens involves 'seizures’ of persons. Only when the officer, by means of physical force or show of authority, has in some way restrained the liberty of a citizen may we conclude that a 'seizure’ has occurred.” Id. at 19 n. 16 (emphasis added). The petitioner has cited no court that has adopted the position that physical force is not available for a Terry stop, and our own search has revealed none. Indeed, of the courts that have addressed the issue, all have concluded that when the Supreme Court used the term "forcible stop,” it meant what it said. See, e.g., United States v. Thompson, 558 F.2d 522 (9th Cir. 1977), cert. denied sub nom., Reeve v. United States, 435 U.S. 914 (1978); United States v. Coades, 549 F.2d 1303 (9th Cir. 1977); United States v. Purry, 545 F.2d 217 (D.C. Cir. 1976); Edwards v. United States, 364 A.2d 1209 (D.C. 1977); Comm. v. Dever, 243 Pa. Super. 87, 364 A.2d 463 (1976). In light of the above, we conclude that the use of reasonable force to effectuate an investigative detention of a suspect is not an impermissible seizure under the fourth amendment to the United States Constitution.
Having determined that there existed specific and articulable facts upon which to found a reasonable suspicion of criminal activity, and that the use of reasonable force to effectuate a valid Terry stop is permissible under the fourth amendment, we affirm the conviction and sentence of the petitioner in this case.
Judgment of the Court of Special Appeals affirmed.
Costs to be paid by petitioner.
. We note from the transcript of the pretrial suppression hearing contained in the record, that Officer McEntee. at one point during his testimony, stated that the radio broadcast reported the fleeing persons to be "two black males.”
. Terry v. Ohio, 392 U.S. 1, 88 S. Ct. 1868, 20 L. Ed. 2d 889 (1968).
. Petitioner relies for this conclusion on the common law doctrine that "one illegally arrested may use any reasonable means to effect his escape, even to the extent of using such force as is reasonably necessary.” Sugarman v. State, 173 Md. 52, 57, 195 A. 324, 326 (1937). However, since we conclude that Officer McEntee possessed authority to make an investigatory stop of the petitioner, we do not further consider this matter. For a discussion of the continuing viability of the common law principle articulated in Sugarman, see Rodgers v. State, 280 Md. 406, 373 A.2d 944 (1977), cert. denied, 434 U.S. 928 (1977); Annot., 44 A.L.R. 3d 1078 (1972).
. The petitioner in the petition for writ of certiorari originally claimed that the Court of Special Appeals erred m assuming that Officer McEntee intended to stop rather than arrest him. Whatever the merit of this contention, the argument, is foreclosed by the statement of facts, agreed upon by the parties pursuant to Maryland Rule 828 g, which places the arrest at a time subsequent to the stopping of the petitioner, as related in the text.
. By this statement, we in no way intimate that there cannot be other combinations of events perceived by an officer that will authorize a Terry stop investigation as being reasonable. The facts of each case will require their own analysis similar to that made here. This is what the Supreme *605Court envisioned would be done when they said in Terry: "[T]here is 'no ready test for determining reasonableness other than by balancing the need to search [or seize) against the invasion which the search [or seizure I entails.’ ” Terry v. Ohio, supra, n. 1, 392 U.S. at 21 (quoting Camara v. Municipal Court, 387 U.S. 523, 536-37, 87 S. Ct. 1727, 18 L. Ed. 2d 930 1967.
. Although not clear from his brief, if the petitioner’s argument is based on the doctrine established by the Supreme Court in Whiteley v. Warden, 401 U.S. 560, 91 S. Ct. 1031, 28 L. Ed. 2d 306 (1971), such reliance is misplaced, for Whiteley involved a challenge founded on the lack of probable cause to arrest, and not the evidentiary requirements necessary for a stop authorized under Terry.