SANTA ANA (CBSLA.com) — Investigators on Friday uncovered a suicide note from an Orange County man who went on a shooting rampage that left three people dead.

KNX 1070’s Mike Landa reports Orange County Sheriff’s investigators believe Ali Syed may not have had a vendetta against his victims.

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A document entitled “Suicide Note” was recovered from a desktop computer from Syed’s bedroom, and was created within an hour of the 911 call from his mother when Syed shot and killed 20-year-old Courtney Aoki of Buena Park Feb. 19.

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Investigators are still trying to determine why Aoki was at Syed’s Ladera Ranch home.

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However, they believe the note indicated Syed’s shooting spree was premeditated.