TUSTIN, Calif. (AP) -- A Southern California college student who fatally shot three people last month before turning the gun on himself wrote a suicide note on his computer indicating the violence was premeditated, authorities said Friday.
The note, found during a forensic examination of Ali Syed's computer, was written within an hour of when police say Syed shot and killed his first victim, a 20-year-old aspiring actress, said Orange County sheriff's Investigator Dan Salcedo.
It showed no evidence, however, of a relationship between Syed, 20, and his three victims, and detectives still believe they were random targets, Salcedo said.
The note showed that Syed had suicidal thoughts and "ideations and premeditations of these random acts of violence" but didn't mention any specific victims, locations or weapons, the investigator said.
Authorities declined to provide more details on the contents of the note.
Deputies found Courtney Aoki dead of multiple gunshot wounds before dawn on Feb. 19 at the home Syed shared with his parents in Ladera Ranch, a prosperous bedroom community in southern Orange County.
As Syed's parents placed a panicked 911 call, Syed sped away in their black SUV and went on to kill two drivers during carjackings, shoot up cars on a busy freeway interchange and injure at least three others before shooting himself in the head, police said.
Investigators still don't know how Aoki got to Syed's house or what she was doing there. They also don't know what time she arrived and aren't sure if she was at the house when Syed wrote his note, Salcedo said.
Syed used a shotgun in his rampage that was given to him by his father as a gift a year earlier, police have said.
Syed, an unemployed part-time community college student, spent hours in his room playing video games, police have said.
The note did not make any mention of video games, Salcedo said.
Earlier this week, police detectives in Tustin -- where one of the three victims was killed -- issued a search warrant for cellphone records of Syed and victim Jeremy Lewis.
Police want to determine if they two had any prior contact, said Lt. Paul Garaven. He declined to provide more details.
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