The parents of British-born Elliot Rodger desperately searched for him as he carried out a deadly gun and knife rampage in Santa Barbara, California, after they received his chilling manifesto, according to a family friend.
Rodger, 22, emailed a 140-page document to several people, including his parents and therapist, just before the shootings began in the town of Isla Vista on Friday night, family friend Simon Astaire told CNN.
Rodger's mother, Lichin, saw the email at 9.17pm local time and immediately went to her son's YouTube page, where she saw a video entitled "Retribution," that he posted on the day of the killings, Mr Astaire told CNN.
Mr Astaire told the news network Rodger's mother called his father Peter, a Hollywood film-maker, before calling 911 and the parents set off for Santa Barbara from Los Angeles.
On the way to the seaside town they heard there was a shooting and later that night, they found out their son was behind the violence, the family friend said.
Rodger is believed to have shot himself in his car after killing six people with a gun and knife and fighting two gun battles with police.