Police have named 22-year-old Elliot Rodger as the suspected gunman who killed six people Friday before taking his own life in a rampage across a California college town, shortly after he posted a threatening video railing against women.

Sheriff Bill Brown described Rodger’s killing spree in the town of Isla Vista as a “obviously the work of a madman," and told a press conference that it was "very, very apparent he was severely mentally disturbed."

Rodger stabbed three people to death in his apartment before gunning down three more victims.

The young man then opened fire on bystanders from his BMW and on foot. Police said the rampage ended when he took his own life after a shootout with sheriff’s deputies.

Thirteen people were also injured in the attack, of whom seven were hospitalised with serious injuries.

The Sheriff identified the suspected killer as the son of Peter Rodger who worked as an assistant director on the box-office record-breaking film “The Hunger Games”.

Prior to the killings, Rodgers had laid out his intentions in a video on YouTube as well as in a 141-page manifesto.

'Rejected by women'

In the video, Rodger bitterly complained of loneliness and the pain he experienced after being rejected by women.

“I’ll take great pleasure in slaughtering all of you,” Rodger said in the video posted Friday, but which was taken down by YouTube on Saturday saying it violated the site’s terms of service.

“I don’t know why you girls are so repulsed by me,” he said, describing the frustration of never having had sex with or even kissed a girl. “I am polite. I am the ultimate gentleman. And yet, you girls never give me a chance. I don’t know why.”

Of the men he viewed as rivals, he said: “I deserve girls much more than all those slobs,” and that after his rampage “you will finally see that I am, in truth, the superior one, the true alpha male.”

The citywide shooting and vehicle-ramming rampage began at about 9.30pm local time on Friday.

His first stop was the Alpha Phi sorority, which he had called “the hottest sorority of UCSB.”

“I know exactly where their house is and I’ve sat outside it in my car to stalk them many times,” Rodger wrote in his extensive manifesto titled “My Twisted World.”

No one answered the door, but he soon shot three women who were standing nearby, killing two of them; 19-year-old Veronika Weiss and 22-year-old Katherine Cooper.

He then drove to a deli where he walked inside and shot and killed another UC Santa Barbara student, 20-year-old Christopher Michaels-Martinez.

Shoot out with police

Michaels-Martinez was the last one killed, but the rampage would continue as Rodger drove across Isla Vista, shooting at some and running down others with his car, twice exchanging gunfire with deputies. He was shot in the hip, but the gunshot to the head that killed him was thought to be self-inflicted, Brown said.

Deputies found three semi-automatic handguns with 400 unspent rounds in his car.

All were purchased legally.

Authorities had been in contact with Rodger three times in the past year, including one case in which he claimed to be beaten but deputies suspected he was the aggressor himself.

On April 30, officials went to his Isla Vista apartment to check on him at the request of his family. But deputies reported back that he was shy, polite and only having a difficult social life but did not need to be taken in for mental health reasons, Brown said. Rodger says in his manifesto: “If they had demanded to search my room... That would have ended everything.”

Family alarmed

Attorney Alan Shifman said the Rodger family had called police after being alarmed by YouTube videos “regarding suicide and the killing of people” that Elliot Rodger had been posting.

Brown called the tragedy “the work of a madman” and said the videotape posted by Rodger the night of the killings is a “particularly chilling one, in which he looks at the camera and talks about what he is about to do.”

Earlier Saturday, Shifman issued a statement saying Peter Rodger believed his son was the shooter.

“The Rodger family offers their deepest compassion and sympathy to the families involved in this terrible tragedy. We are experiencing the most inconceivable pain, and our hearts go out to everybody involved,” Shifman said.

(FRANCE 24 with AP, REUTERS)