OPINION OF THE COURT
Boomer, J.Defendant appeals from a judgment, entered upon a jury verdict, convicting him of murder in the second degree. He raises issues concerning his warrantless arrest in his home and the seizure of certain items pursuant to a search warrant. Defendant contends that the initial entry into his home was illegal and that the police exploited the illegality in obtaining his statement and in applying for the search warrant. Consequently, he argues, the suppression court committed reversible error in refusing to suppress the statement and the items seized pursuant to the search warrant. We disagree.
I
The testimony at the suppression hearing shows that the police first learned about the murder of John Borek from a *7friend of defendant’s, Timothy Murray, who came to the police station with his father and gave a detailed statement. Murray recounted that the night before he, along with defendant, defendant’s girlfriend, Borek, and others were drinking wine and smoking marihuana in defendant’s apartment. After the others left, defendant, in the presence of his girlfriend and Murray, assaulted Borek with a table leg, knocking him to the floor. Defendant got on top of Borek and stabbed him in the thigh with a buck knife. He then ordered Murray to tie Borek’s hands and leg with extension cords and he, his girlfriend, Murray and Borek left the apartment. Outside, defendant’s girlfriend left and defendant and Murray walked some distance with Borek to an isolated area. There, after causing Murray to undress Borek, defendant stabbed Borek in the eyes, arms, mouth, chest, and throat and began jumping upon his chest yelling, "Come on, die. Come on, die.” When Borek stopped breathing, defendant ordered Murray to remove a sewer cover and to help him throw the body into the sewer. Defendant and Murray then walked to a reservoir where defendant threw Borek’s clothes and the buck knife into the water. Murray also told the police that defendant said he was going to Houston, Texas.
The police went to the sewer described by Murray where, at 10:30 p.m., they found Borek’s body. Murray’s statement was transcribed and sworn to at 11:45 p.m., and between 12:30 and 12:45 a.m. the Chief of the Homicide Bureau directed the police to arrest defendant. The Chief decided to have defendant arrested at his apartment without a warrant because, in view of Murray’s statement that defendant intended to leave town, the hour of the night, and the unavailability of a Judge, there was no time to obtain a warrant. Following the Chiefs instructions, the police went to defendant’s apartment and knocked on the door. Although they heard movement inside, there was no response, so the officers tried to kick in the door and then had firemen pry it open. Inside they found defendant hiding under a bed and when he emerged, he shouted, "I didn’t kill him, Timmy Murray did.”
After arresting defendant, one of the officers looked in defendant’s clothes closet and noticed a knapsack. The officer also picked up a jacket which was hanging on the back of the bedroom door.
The next morning, the Chief directed a police officer to obtain a warrant to search defendant’s apartment. The only information the officer had concerning the crime was Mur*8ray’s sworn statement, and to establish probable cause, he attached a copy of that statement to the application for the warrant. Following the issuance of the warrant, police searched the apartment and seized a navy blue pea coat, two extension cords, and a coffee table and table leg. After defendant was arrested and before the search warrant was issued, the police took photographs showing the layout of the apartment. Only the extension cords, the table leg, and the photographs were introduced at trial.
At trial, defendant’s girlfriend corroborated Murray’s testimony that defendant, while on top of Borek, stabbed him in the thigh and that defendant, Murray, and Borek left the area of the apartment together. The police testified that they found Borek’s clothes in the reservoir and on top of the clothes, the blade of a knife. Defendant was known to carry a knife in a case attached to his belt.
II
Based upon the testimony at the hearing, the suppression court properly found that the arrest of defendant in his home without a warrant was justified because of exigent circumstances.
Although, absent a warrant, the police may not make a routine arrest within a person’s home, a warrant is unnecessary under "exigent circumstances” (Steagald v United States, 451 US 204, 221; Payton v New York, 445 US 573, 590). The Supreme Court has not adopted any criteria for determining the existence of exigent circumstances, but other courts have given us some guidelines. Although not to be taken as a rigid formula, the following factors should be considered in determining whether exigent circumstances exist: (1) the gravity or violent nature of the offense; (2) whether there is reason to believe the suspect is armed; (3) whether there is a clear showing of probable cause; (4) whether there is strong reason to believe the subject is in the premises being entered; (5) the likelihood the suspect will escape if not swiftly apprehended; and (6) the peaceful circumstances of the entry (United States v Campbell, 581 F2d 22, 26; Dorman v United States, 435 F2d 385, 392-393; People v Gordon, 110 AD2d 778, 780; see also, People v Martin, 50 NY2d 1029, 1031, n 2).
Here, (1) the crime, a savage murder, was grave and violent; (2) the subject was armed with a knife when he committed the murder and there was no reason to believe he would not have *9access to a knife in his apartment; (3) the showing of probable cause that defendant had committed a murder was clear; (4) there was strong reason to believe defendant was in his apartment because Murray had said that he and defendant returned to the apartment after the murder, and when the police knocked on the door they heard someone inside; (5) there was a likelihood defendant could escape if not swiftly apprehended because Murray had told the police that defendant said he was going to leave for Houston, Texas; and (6) although the police used force to gain entry, the use of force does not preclude a warrantless entry (Dorman v United States, supra, p 393). Here the entry did not provoke a confrontation. The police first knocked on the door and announced their presence, and only when there was no response did they kick at the door and have the firemen pry it open. Another circumstance adding to the exigency was that after the police had found the body and had thus obtained clear probable cause, it was close to midnight and it was unlikely that, at that time, they could obtain a warrant expeditiously.
It may be argued that to prevent defendant’s escape, the police should have guarded the premises and waited until morning to obtain a warrant. This argument was found unreasonable in United States v Campbell (581 F2d 22, 26-27, supra), where the court stated: "Moreover, had the officers decided to set up surveillance of the apartments while waiting for a warrant to be issued, they would have risked the possibility of detection by appellants. If appellants had been alerted to the presence of the police, they might well have had sufficient time to dispose of the stolen money and other evidence in their possession. Furthermore, the risk of an armed confrontation would have thus been heightened. To secure a warrant would have required the police and agents to wait at least several more hours until the facts were fully communicated to headquarters, typed in affidavit form, attested to, presented to one of the district’s busy magistrates, and a warrant obtained in due course.”
In Campbell (supra), the court stressed the reasonableness of the police action in waiting to make the arrest until they had fully investigated the crime and obtained clear probable cause. Here, the police acted reasonably in investigating Murray’s accusations by going to the scene of the murder where they found the body and by taking a detailed sworn statement from Murray. Only then did they have clear probable cause to make the arrest.
*10Since there were sufficient exigent circumstances to justify the warrantless entry and arrest, there was no basis for the suppression of defendant’s statement that Murray, not he, had committed the crime.
Ill
Nor was there any basis for suppressing the items seized pursuant to the search warrant. Even if the initial entry were held to be illegal, there was no showing that the search and seizure following the issuance of the warrant was tainted by the illegality. As Judge Jasen wrote in People v Arnau (58 NY2d 27, 32, cert denied 468 US 1217), because the exclusionary rule exacts a heavy price, "courts have long held that only evidence which ' "has been come at by exploitation of that illegality” ’ should be suppressed. (Wong Sun v United States, 371 US 471, 488, quoting Maguire, Evidence of Guilt [1959], p 221; 3 LaFave, Search & Seizure, § 11.4, p 613.)” Here, in obtaining the search warrant, the police did not exploit the initial entry. The officer applying for the warrant had received no information about the crime other than the facts contained in Murray’s sworn statement and the application was based solely upon that statement. Further, there was no indication that the items introduced into evidence at trial and seized after the issuance of the search warrant were either discovered or seized during the initial entry.
The only items of evidence the police obtained from the apartment before they obtained the search warrant were the photographs of the interior of the apartment. These photographs depict no incriminating evidence and were used at the trial only to show the layout of the apartment. Defendant has not suggested that he was in any way prejudiced by their use at trial.
IV
Further, even if defendant’s warrantless arrest were illegal and his statement therefore should have been suppressed, that error would be harmless. The proof that defendant and Murray were together before and during the time that the victim was killed was overwhelming. Under the circumstances, defendant’s only line of defense was to point to Murray as the killer. So viewed, his statement to the police that Murray did it was exculpatory rather than inculpatory. Thus, there was no reasonable possibility that the error might *11have contributed to defendant’s conviction (People v Crimmins, 36 NY2d 230, 237).
We have examined the other arguments made in defendant’s brief and in his supplemental pro se brief, and we conclude that they do not warrant reversal. Accordingly, the conviction should be affirmed.