Commissioner Charles H. Ramsey and Mayor Nutter announced the restriction of duty at a news conference late yesterday afternoon in front of Police Headquarters.

Ramsey said that the five officers had been seen participating in the beating, and that the sergeant had been removed from duty "for failing to take supervisory action to intervene."

Their names were not released.

Ramsey said other officers would likely be removed from duty as they were identified from the 11-minute video, which Fox29 first aired Tuesday morning.

The video, shot from a helicopter over the 4500 block of North Fourth Street in Feltonville, shows about 15 police officers participating in the beating or standing by the suspects' stopped sedan as the suspects are repeatedly kicked and punched.

A copy of the video and the department's evidence involving the six have been referred to the District Attorney's Office for possible criminal prosecution, Ramsey said.

Cathie Abookire, spokeswoman for District Attorney Lynne M. Abraham, said the matter was under investigation and declined to elaborate.

The six were identified from the video and reviews of patrol vehicle logs and tapes of radio communications, Ramsey said.

He said the department hoped to get an enhanced copy of the video last night to enable investigators to identify other police involved. In the meantime, the Internal Affairs Unit is probing the matter.

Nutter, as Ramsey did Tuesday, tried to provide some context to the incident.

On Saturday, police were mobilized to look for the killer of Sgt. Stephen Liczbinski, shot earlier in the day.

On Sunday night, a 20-year-old man was shot and killed in Feltonville, a section of North Philadelphia. The killing was followed by street talk of "payback" planned for Monday night. That retaliation, a drive-by shooting, happened about 10 Monday night and wounded three people. Narcotics officers, however, saw the shooting and chased the three suspects. Other units joined them.

Still, Nutter said, "there are certain standards of professionalism in the way you conduct a proper arrest."

"The behavior, at least the behavior exhibited on the tape, is unacceptable," he added.

The dramatic nature of the video made it a national story, featured prominently last night on the ABC News with Charles Gibson. The story was also picked up in Europe, including coverage by the BBC.

"I honestly don't know what else can be said," Nutter spokesman Luke Butler said last night about the attention on the city. "Both the mayor and the commissioner have been very clear about the context in which this occurred."

In fact, yesterday's news conference was called in part to answer requests from national reporters for comment. Nutter and Ramsey said the arrest, while not excusable, had occurred at a time of high stress for the city's police officers.

The Police Advisory Commission, the watchdog agency created to improve police-community relations and investigate citizen complaints, announced yesterday that it would monitor the internal investigation.

Executive director William Johnson said the commission would provide the Police Department with recommendations about support services and deployment of police after officer shootings.

"When you consider the circumstances in Philadelphia over the last few days, coupled with officers' heightened sense of safety for themselves, there is a need to rethink who is being deployed, for how long, and whether or not certain officers should even be responding to these kinds of situations at this time," commission chairman Robert S. Nix said.

The three men apprehended Monday night remained in custody yesterday. According to court records, each was charged with multiple counts of attempted murder, conspiracy, aggravated and simple assault, recklessly endangering another person, and firearms violations.

They were identified as Dwayne (sometimes spelled Dawayne) Dyches, 24, of the 2000 block of North Marshall Street in North Philadelphia; Brian Hall, 23, of the 1900 block of North Marshall Street; and Pete Hopkins, 19, of the 2000 block of East Firth Street in Kensington. Bail was $500,000 for Dyches, $400,000 for Hopkins, and $100,000 for Hall.

When arrested, Dyches was out on bail awaiting trial on three drug-possession cases, tentatively scheduled for this month and next. Hopkins was out on bail awaiting trial on a charge of criminal trespass.

D. Scott Perrine, a Center City lawyer who says he is representing the three men, has said police did not have probable cause to follow and arrest the three and had no excuse for beating and kicking them.

Perrine said his clients had nothing to do with the shooting. He said police had assumed they were participants because they had driven away shortly after the shooting.

Police, however, said officers had watched the vehicle from the time it arrived at Fourth and Annsbury Streets in Feltonville about 10 p.m. Monday to when an occupant fired on a group of people gathered there. Police have not identified the three who were wounded because they are crime victims.

The unidentified shooter - who was still at large last night - fled on foot, and the vehicle, a 2000 Mercury Grand Marquis, sped off. The officers followed the vehicle.

Police said they had found fifteen 9mm cartridge casings at the shooting scene. No gun was found in the vehicle.

The car was stopped about two miles away, where, as depicted in the Fox29 video, about 15 officers rushed to it and pulled the three men out, kicking and hitting them while they were on the ground until they were handcuffed.