Modesto police interviewed victims and witnesses Monday as part of their investigation into a weekend assault downtown that sent two women to the hospital.
The women, ages 20 and 25, have been released.
The incident happened near 12th and L streets early Sunday.
Police said one victim was beaten unconscious and kicked in the head; the other woman was raped. Surveillance videos captured the attack.
Four men in a sport utility vehicle were arrested less than a block from the scene:
Ruben Leonard Moreno Jr., 23, on suspicion of attempted homicide and committing a felony while on bail
Ricardo Garcia, 21, on suspicion of aiding in a felony and kidnapping
Emanual Alvarez, 21, on suspicion of aiding in a felony, rape and kidnapping
Felix Rangel, 21, on suspicion of aiding in a felony, kidnapping and committing a felony while on bail
Lt. Chris Fuzie said more charges could be added. He urged anyone with information to call Detective Steve Anderson at 342-9173 or Crime Stoppers toll free at 866-602-7463. Callers to Crime Stoppers can remain anonymous and may be eligible for a cash reward.