(CNN) -- A file titled "Suicide Note" was recovered from the desktop computer in the bedroom of a man called responsible for the killings of three people in Orange County, California, last month, authorities said Friday.
The note had indications that Ali Syed was responsible for premeditated and planned acts, according to Orange County Sheriff-Coroner Sandra Hutchens. "Although this investigation will continue, to date, Orange County Sheriff's homicide investigators have not found any prior connection/relationship between Syed and any of his victims."
The suicide note was created within an hour of a 911 call from the suspect's residence, authorities said of a preliminary computer forensic analysis.
Police say they believe Syed, a part-time college student, fatally shot a woman at his family's Ladera Ranch home before killing two other people.
The February 19 shooting spree ended when Syed died after he turned his gun on himself as police approached on a road north of Tustin, authorities said.
CNN's Miguel Marquez contributed to this report.