OPINION OF THE COURT
ALITO, Circuit Judge:Jesse Kithcart appeals from a judgment in a criminal case. Kithcart pled guilty to one count of being a felon in possession of a firearm, in violation of 18 U.S.C. § 922(g)(1), but he reserved his right to appeal the district court’s decision on his motion to suppress the firearm in question. This appeal raises the question whether the officers had probable cause to arrest and search Kithcart. Because we conclude that they did not have probable cause, we reverse the district court’s denial of the suppression motion on the grounds given, and we remand for further proceedings in accordance with this opinion.
I.
On July 25, 1995, Bensalem Township Police Officer Teresa Nelson was assigned to a radio patrol car on the evening shift. Over the course of an hour, Officer Nelson received three radio transmissions, each reporting an armed robbery. The first two robberies occurred at motels in Bensalem Township, and the last transmission concerned a robbery in neighboring Bristol Township. The final report — which was received at approximately 10:43 p.m. — did not *530specify either the time or location of the Bristol robbery. Bristol is north of, and adjacent to, Bensalem Township.
The alleged perpetrators of these robberies were described as “two black males in a black sports car.” It was also reported that one of the perpetrators might have been wearing white clothes, and the vehicle was described as a “possible Z-28, possible Cá-maro.”1
At 10:53 p.m. — approximately ten minutes after receiving the final radio transmission regarding the Bristol robbery — Officer Nelson spotted a black Nissan 300ZX, which she described as a sports car, traveling south on Route 13, approximately a mile or less from the boundary of Bristol Township. The vehicle was driven by an African-American male who appeared to be the only person in the car. Officer Nelson testified that since the time when she received the first radio transmission more than an hour earlier, this was the first occasion when she spotted either a black vehicle or a black male driving a car. Officer Nelson also testified that immediately after she pulled up behind the vehicle, which had stopped at a red light, the driver drove the Nissan through the red light. Officer Nelson then flashed her dome lights, and the Nissan pulled over to the side of the road. At this point, Officer Nelson saw two sets of arms raised toward the roof of the ear, and she realized that there were two people in the car.
Officer Nelson then called for backup and waited in her patrol car until Officers Christine Kellaher and Bill Williams arrived at the scene. Officer Williams found a gun in Kith-cart’s white nylon waist pouch, and Officer Kellaher found a gun under the driver’s seat.
In moving to suppress the evidence seized by the police, Kithcart contended among other things, that the police lacked reasonable suspicion for an investigatory stop pursuant to Delaware v. Prouse, 440 U.S. 648, 99 S.Ct. 1391, 59 L.Ed.2d 660 (1979), Terry v. Ohio, 392 U.S. 1, 88 S.Ct. 1868, 20 L.Ed.2d 889 (1968), and related cases. See App. 95a. Consistent with this argument, Kithcart argued that Officer Williams had discovered his gun during a “pat down” or “frisk” but that the standard for conducting a “frisk” under Terry had not been met. App. 97a. The government argued that the police were justified in stopping the car because the driver ran a red light. In addition, the government’s brief argued as follows:
[Gjiven that Officers Nelson and Williams were confronted with two black males in a black sports car shortly after and in the vicinity of the reported robberies, and that the males had attempted to flee upon seeing Officer Nelson’s car pull behind theirs, the totality of the circumstances established reasonable suspicion to support the pat-down of the defendant and his waist-pack. See Chimel v. California, 395 U.S. 752, 763, 89 S.Ct. 2034, 2040, 23 L.Ed.2d 685 (1969) (lawful arrest creates a situation which justifies a contemporaneous search of arrestee and immediate area, including area from within which arrestee might gain possession of a weapon); Terry v. Ohio, 392 U.S. 1[, 88 S.Ct. 1868, 20 L.Ed.2d 889] (1968) (limited pat-down of a suspect’s exterior clothing and protective sweep of area within immediate control are authorized during a lawful stop).
App. 107a-108a.
At the hearing on the motion, counsel for Kithcart, counsel for the government, and the court all referred to the government’s latter argument as concerning the question of “probable cause” (see e.g., App. 27a, 28a, 54a, 58a), and at the conclusion of the hearing,2 the district court orally ruled that the police had “probable cause ... for the stop.” App. 60a. The court relied on “the direction, the timing, the location of the vehicle, plus the fact it [was] a black sports car.” App. 60a. The court noted the discrepancy be*531tween the radioed description of the perpetrators as two black males and Officer Nelson’s initial belief that there was only one black male in the car, but the court held that the fact that Officer Nelson had not seen any other black men driving cars since she received the initial radio transmission heightened the probability that the driver of the vehicle had been involved in the robberies. Because the court concluded that the officers ■had probable cause, the court found it unnecessary to decide whether the alleged running of the red light provided an independent básis for Officer Nelson’s stop and the subsequent actions of the officers.
Following this ruling, Kithcart pled guilty;' subject to the condition that he be allowed to " challenge on appeal the district court’s denial of his motion to suppress.
II.
We turn first to the ground on which we understand the district court to have denied Kithcart’s suppression motion, viz., that the officers had “probable cause” to arrest Kithcart and to search him incident to the arrest. When a warrantless search is made pursuant to an arrest, “[t]he constitu: tional validity of the search ... must depend upon the constitutional validity of the ... arrest.” Beck v. Ohio, 379 U.S. 89, 91, 85 . S.Ct. 223, 225, 13 L.Ed.2d 142 (1964).
Whether that [warrantlessj arrest `cvas constitutionally valid depends in turn upon whether, at the moment the arrest was made, the officers had probable cause to, make it-whether at that moment the facts and circumstances within their knowledge, and of which they had reasonably trustworthy information were sufficient to warrant a prudent man in believing that the [suspect] had committed or was committing an offense.
Id. See also Barna v. City of Perth Amboy, 42 F.3d 809, 819 (3d Cir.1994) (test for probable cause is objective test: did the police officer have a reasonable basis for believing that the suspect had committed or was committing a crime). Our review of a district court’s determination that there was probable cause to effect a warrantless search is de novo. Ornelas v. United States, 517 U.S. 690,-, 116 S.Ct. 1657, 1659, 134 L,Ed.2d 911 (1996).
Based on the standard set by the Supreme Court in Beck, the district court erred in concluding that there was probable cause to arrest and search Kithcart prior to the discovery of the guns. The mere fact that Kithcart is black and the perpetrators had been described as two black males is plainly insufficient. As we have previously noted, a description of “ ‘two negro males’ and two ‘black males’ ... without more ... would not have been sufficient to provide probable cause to arrest [the suspect].” Edwards v. City of Philadelphia, 860 F.2d 568, 571 n. 2 (3d Cir.1988). Moreover, the match between the description of the perpetrators’ car (a black sports car, “possible Z-28, possible Camaro)” and the vehicle in which Kith-cart was spotted (a black Nissan 300ZX) was far from precise. Although the Camaro Z-28 and the Nissan 300ZX could be considered . “sports cars,” there was no evidence offered at the suppression hearing that the shapes of the two cars were sufficiently similar so as to warrant an inference that a 300ZX could be mistaken for a Z-28.
Nor is probable cause established by either the location or time of the stop. There was no evidence presented as to where in Bristol Township the final robbery occurred; nor was there evidence presented that the Bristol robbery occurred shortly before Officer Nelson stopped the car carrying Kithcart. Al- - though the radio transmission regarding the Bristol robbery came approximately 10 minutes before the vehicle was stopped, Officer •Nelson testified that she did not recall that • the radio transmission revealed when the Bristol robbery occurred, other than that it occurred that same evening. Compare Edwards, 860 F,2d at 571 n. 2 (although the description “two negro males” was insuffi- ' cient by itself to provide probable cause to arrest suspect, other evidence closely linking suspect to scene of reported crime was suffi- ’ cient). In sum, we think that it is clear that the facts and circumstances within Officer Nelson’s knowledge at the time she stopped the Nissan were insufficient .to allow a prudent person to believe that the car and its ■ occupants had committed or were committing *532an offense. In other words, armed with information that two black males driving a black sports car were believed to have committed three robberies in the area some relatively short time earlier, Officer Nelson could not justifiably arrest any African-American man who happened to drive by in any type of black sports car.
III.
The finding of no probable cause, however, does not end the inquiry. In Terry v. Ohio, supra, the Supreme Court held that law enforcement officers may stop and temporarily detain persons short of arrest without violating the Fourth Amendment. A Terry stop is justified when an officer has a reasonable suspicion that “criminal activity may be afoot.” Id. at 30, 88 S.Ct. at 1884. The officer’s suspicion must be based on articula-ble facts and not merely the officer’s subjective good faith. Id. at 21, 88 S.Ct. at 1879-80. An officer may also conduct a “reasonable search for weapons for the protection of the police officer, where he has reason to believe that he is dealing with an armed and dangerous individual....” Id. at 27, 88 S.Ct. at 1883. The test is “whether a reasonably prudent man in the circumstances would be warranted in the belief that his safety or that of others was in danger.” Id. As noted, this question was briefed by the parties in the district court, but the district court did not base its decision on this ground.
On remand, the district court should examine whether Officer Nelson had a reasonable suspicion sufficient to warrant an investigative stop. The court should consider both of the government’s asserted grounds for the stop: (1) the alleged traffic infraction and (2) the information regarding the armed robbery suspects discussed in Section II, infra. The district court should also consider whether the events leading to the discovery of the weapon in Kithcart’s pouch can be justified as a Terry “pat-down”. We offer no opinion at this juncture on any of these questions.
IV.
For the foregoing reasons, we conclude that the district court erred in finding that Officer Nelson had probable cause to arrest and search Kithcart. We therefore reverse the denial of the suppression motion and remand for further proceedings to consider whether the officers had reasonable suspicion for an investigative stop and weapons search of Kithcart’s person.
. The Z-28 is a type of Camaro.
. Officer Nelson testified at the hearing. Officers Kellaher and Williams did not testify. Officer Nelson's account of the traffic violation was disputed by the defense. Co-defendant Carl Green — the driver of the car and a cooperating witness against Kithcart — told the government that he had not driven through a red light prior to the stop by Officer Nelson. The district court did not resolve this issue, relying instead on its finding that there was probable cause to arrest and search based on the radio transmissions.