"We just have to be patient and see whatever comes and react," McMahon said.
If prosecutors agree, McCoy and three friends will be charged with aggravated assault and other crimes, a police official said Tuesday night.
In the video, posted Tuesday morning, a man in a black T-shirt can be seen entering a scrum and reaching back to throw a punch toward someone on the floor. The person throwing the punch has his back to the camera and his face cannot be seen.
At another point in the video, which appears to have been shot with a cellphone, a man resembling McCoy can be seen shouting while being restrained by several men.
TMZ reported that police sources confirmed the video contains footage of the brawl.
Jeff Chrusch, of the police public affairs office, would not say whether authorities had seen the video or were using it as part of their investigation.
"The department is reviewing all video information that we have obtained," he said.
Two off-duty officers were injured in the fight, which apparently erupted after a member of McCoy's entourage argued with an officer about a bottle of champagne, according to incident reports.
McCoy, 27, and three other men "punched, kicked, and stomped" the officers after the argument, according to incident reports. The other men were former San Diego Chargers running back Curtis Brinkley, 30; former University of Pittsburgh wide receiver Tamarcus Porter, 27; and Christopher Henderson, 26.
Officers Darnell Jessie and Roland Butler, both 11-year veterans, were hospitalized Sunday for injuries including a potential skull fracture and broken ribs. Police Sgt. Daniel Ayres also was apparently caught in the brawl but was uninjured, according to incident reports.
Surveillance cameras at the nightclub where the fracas occurred weren't working Sunday, police reports said.
Cameron Kline, spokesman for the District Attorney's Office, declined to say what evidence prosecutors were reviewing, or whether McCoy or anyone else had been questioned during the police investigation.
Staff writer Robert Moran contributed to this article.