Police Lt. Lyn Tomioka says Ed Perkins of San Francisco is in custody on suspicion of murder.

Perkins was arrested at the scene after 19-year-old Stephen Powell was shot multiple times and two others suffered gunshot wounds to the leg at a street party in the Castro district late Saturday night. Police recovered a handgun in the shooting.

Tomioka would not say if investigators believe Perkins was the shooter, nor would she confirm if there are other suspects.

Police believe the shooter knew Powell. They say the other two victims --- a 19-year-old woman and a 29-year-old man --- were innocent bystanders.

Police do not suspect the shooting was a hate crime.