Police are conducting ballistic tests to determine whether more than one gun was used in a shooting inside a hip-hop concert in New York featuring artist TI that killed one person and injured three others.
Among those tests was an analysis of a bullet removed from the leg of rapper Troy Ave, who remains in hospital following his arrest on attempted murder and weapons charges in the Wednesday night shooting.
No weapons have been recovered, though tests have found that five 9-mm shell casings discovered at the scene belong to the same gun.
Troy Ave, whose real name is Roland Collins, suffered a gunshot wound to the leg. One of his security guards, 33-year-old Ronald McPhatter, was killed in the shooting. Two others were shot and injured.
A spokeswoman for Manhattan prosecutors said she did not know when Collins would be arraigned.
An eight-second video clip released by police shows a limping gunman - identified by the police as Collins - burst through a VIP room door, stop and scan the room, then raise his gun and fire a single round.
There were nearly 1,000 concertgoers in the building at the time of the shooting and witnesses described a chaotic scene as people rushed towards the exits.
It is not yet known for certain what sparked the violence, according to officials.
McPhatter's brother, Shanduke McPhatter, said his brother "got too much into" the glamour of the hip-hop scene, and it landed him in an environment where alcohol flowed freely and trouble broke out.