Authorities arrested a 29-year-old man on suspicion of voluntary manslaughter after he allegedly left a 26-year-old Aptos man in the water.
Just before 9 a.m. Wednesday, sheriff's deputies and officers with California State Parks learned two boats collided in the harbor.
The victim allegedly boarded the suspect's boat, and a physical altercation ensued between both. The victim fell into the water as the suspect allegedly hit him with a stick. The victim remained in the water and the suspect left the area, according to the Sheriff's Office.
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A passing vessel attempted to rescue the victim by trying to throw him a life preserver, but they were unsuccessful.
The Sheriff's Office's dive team, assisted by the U.S. Coast Guard and a sonar device, recovered the victim's body from the harbor at about 1:20 p.m. Wednesday. Deputies said the county coroner's office will do a forensic examination to determine the victim's cause of death.
The suspect has been booked into the Monterey County Jail in lieu of $200,000 bail.
Anyone with information about the suspected homicide can anonymously contact Detective Josue Ramirez at (831) 253-6068.