By Chelsea J. Carter
(CNN) — In the aftermath of a shooting rampage in a Southern California college town, investigators want to know two things: Who was the man behind the gun, and why did he kill six people and wound seven others?
Authorities have not released the identity of the gunman, who they say died from a gunshot wound to the head following a shootout with police during the rampage in Isla Vista, near the University of California, Santa Barbara.
But based on what police have told the family of 22-year-old Elliot Rodger, the parents believe he is the man behind the shootings, attorney Alan Shifman, the family spokesman, told reporters on Saturday.
A portrait of a disturbed young man has begun to emerge as investigators piece together details about the shooter.
“The sheriff’s office has obtained and is currently analyzing written and video evidence that suggests this was a premeditated mass murder,” Santa Barbara sheriff’s spokeswoman Kelly Hoover said.
Santa Barbara Sheriff Bill Brown called the suspect “severely mentally disturbed,” according to CNN affiliate KEYT.
Authorities searching for a motive were looking into a video posted on social media that contains a man’s tirade against women who supposedly rebuffed him, Brown told the station. Hoover said the suspect has been preliminarily identified but his name won’t be released until “a positive identification is made.”
Part of that evidence appears to be a chilling YouTube video titled “Retribution” posted by a young man who rants for nearly seven minutes against women who he says ignored and rejected him.
“Tomorrow is the day of retribution. The day in which I will have my revenge against humanity, against all of you,” the man said.
In the video, the man lays out a play to kill blond sorority girls.
Authorities have not identified those killed or wounded in the shooting spree.
This much is known: The rampage began at about 9:27 local time Friday night in Isla Vista, a popular area near the coast bustling with activity at the start of the Memorial Day weekend.
Witness Robert Johnson told CNN he was standing on a corner when he heard what he thought were fireworks. Then a black BMW with tinted windows drove by and either slowed down or stopped outside a deli where as many as eight people were eating outside.
Someone opened fire from the car, he said.
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