Elliot Rodger: Did Police Miss Their Chance?

Police have admitted Elliot Rodger was "severely mentally disturbed" - so were opportunities missed to stop his killing spree?

Santa Barbara sheriff Bill Brown told reporters they had encountered Rodger three times - the most significant on April 30 when a family member asked police to check on him.

"(Police) found him to be polite and courteous. He downplayed the concerns for his welfare and the deputies cleared the call," said Sheriff Brown.

Rodger regularly posted "selfie" photos on social media

"They determined he did not meet the criteria for an involuntary mental health hold. He appeared timid and shy."

In his rambling online 'manifesto', Rodger describes his relief that his plans for murder had not been discovered.

The killer pictured in the BMW he used in his killing spree

"For a few horrible seconds I thought it was all over," writes the 22-year-old, who says his plans for a "Day of Retribution" began last summer when he claims he was attacked at a party.

In pictures posted on social networking websites, Rodger appeared to be a privileged young man who enjoyed the trappings of his Hollywood filmmaker father's success.

The 22-year-old pictured recently with his filmmaker father Peter

In reality, he was documenting his inner torment and making painstaking preparations for the killing spree that left six innocent people dead in knife and gun attacks.

Rodger described taking down his YouTube videos to head off suspicions over his mental health.

Police told reporters the killer said he was having social problems and would not be returning to school for the next year.

Rodger (L) attended the 2012 Hunger Games premiere with his father (R)

"The deputies discussed options available to him in terms of support offered", said Sheriff Brown, who added such call-outs were a routine part of the job.

The Rodgers' family lawyer, Alan Shifman, said Elliot had been diagnosed with Asperger's syndrome - a form of autism - at a young age.

"He was probably a victim, from my understanding, of bullying throughout his life," said Mr Shifman. "I am sure that played a role in the terrible consequences of last night.

The student, circled in a fifth grade photo, was bullied, his family said

"He had multiple therapists - a social worker who as recently as last week was concerned."

The killer's online post - which runs to more than 140 pages - reveals the extent of his mental illness. Police have described it as a "combination of an autobiography and diary".

He repeatedly describes his hatred of women and his frustration at being ignored and remaining a virgin while girls around him choose "obnoxious" men, or men he considers racially inferior.

The killer posted a picture of himself on a visit to London in 2011

"Women are sexually attracted to the wrong type of man," he writes.

"Obnoxious, tough jock-type men. They should be going for intelligent gentlemen such as myself ... This is a major flaw in the foundation of humanity."

The final section of his post is entitled: 'Part 6: Santa Barbara: Endgame Age 19-22'.

Rodger attended a 'private' Katy Perry concert in March 2012

He sets out his plans to "silently kill as many people as I can by luring them into my apartment through some sort of trickery".

Rodger also talks of beheading and torturing his victims, as well as killing all the members of the Alpha Phi sorority.

"I will punish all females for the crime of depriving me of sex," he writes.

The young man appeared to enjoy the trappings of his father's success

Police revealed he tried unsuccessfully to enter the sorority and that the women inside heard "loud, aggressive knocking" for several minutes but did not open the door.

With his plan seemingly frustrated, Rodger shot three young female students, killing two - Katherine Cooper, 22, and Veronica Weiss, 19.

He then went on a shooting spree through Santa Barbara, killing one more victim, Christopher Michael-Martinez. Seven people also remain in hospital, two with serious injuries.