Parents of Santa Barbara Killer Rushed to Intervene, But Too Late Elliot Rodger sent email to parents before alleged rampage.

May 25, 2014 -- Elliot Rodger's parents raced to find their son Friday night after they got his chilling email outlining a plot to go on a killing spree, but it was too late. Rodger had already set in motion his rampage, including the killing of six people and the wounding of 13 others.

Chin Rodger, his mother, got a call from Elliot's therapist at 9:17 p.m. Pacific Time Friday, just minutes before the 22-year-old student opened fire outside a Santa Barbara, California, sorority house, according to police.

"Have you gotten Elliot's email?" the therapist said, as recounted by Simon Astaire, a close family friend. "I think you should see it."

The email contained links to 137-page manifesto Elliot wrote and conveyed that something was terribly wrong. Astaire, a writer who has served as a media adviser to high-profile individuals, gave this information to ABC News and other media outlets on Sunday.

Read: Father of Santa Barbara Victim Sobs and Rails Against Son's Death

The alleged shooter's mother then checked Elliot's YouTube channel and found videos including "Elliot Rodger's Retribution," outlining his alienation and loneliness at being spurned by women and his revulsion for happy couples when he had no female companionship.

"On the day of retribution I am going to enter the hottest sorority house of UCSB and I will slaughter every single spoiled, stuck-up blond slut I see inside there," he said in one video.

Read: Elliot Rodger's Trail of Carnage

An alarmed Chin Rodger called her ex-husband Peter with the news and they immediately set out for their son's apartment outside Santa Barbara. According to Astaire, the parents notified authorities and summoned them to their son's apartment. But by then, he said, news of the rampage had already been reported on their car radio.

The parents had previously called police to report bizarre behavior by their son.

Rodgers was most recently visited and interviewed by the police in April after a family member became alarmed about YouTube posts by Rodger that mentioned violence and suicide. While Rodger's parents and social worker were concerned, police found the student to be polite during their interview. He had taken down the alarming posts. Police cleared the call and left without taking any action.

Read: Police action on rampage killer complaints questioned.

The family never suspected Elliot would have guns, Astaire said: "He had no affinity, it seemed, to guns whatsoever." But in fact the young man had stockpiled at least four guns and hundreds of rounds of ammo in his room, all bought legally.

According to Astaire, Elliot was a loner who had trouble connecting with people. "He was fundamentally withdrawn," Astaire said.

In the text that his parents saw Rodger, 22, detailed his plans for revenge against women where he planned to kill as many people as possible, including members of a sorority house, his brother and stepmother, and then take his own life.

READ: Friend says Santa Barbara Killer Was Loney Guy

"'How dare those girls give their love and sex to those other men and not me,' I constantly think when I see young couples," wrote Rodger. "There is nowhere in the world I can go anymore."

The perceived rejection apparently fueled Rodger's rage and the student wrote he felt that humanity had rejected him.

"The females of the human species have never wanted to mate with me, so how could I possibly consider myself part of humanity?" wrote Rodger. "Humanity has never accepted me among them, and now I know why. I am more than human. I am superior to them all. I am Elliot Rodger … Magnificent, glorious, supreme, eminent … Divine!"

"There is something very wrong with that. It is an injustice that cannot go unpunished," wrote Rodger of the perceived rejection.

Rodger was found dead after a shootout with police. Today, police said they were not yet sure if the suspect was killed by his own gun or that of a police officer.

ABC News' Micah Grimes contributed to this report.