A man is dead after his boat slammed into a Mission Bay Pier early Wednesday morning, reportedly the victim of a throttle mishap.

According to KCBS, a distress call was made from the area of Pier 52 at 6:13 this morning. When San Francisco Fire crews responded, they learned that a boater had struck the pier, possibly with fatal results.

SFFD spokesperson Mindy Talmadge tells SF Weekly and the Chron that a witness saw the boat's driver "slumped over the steering wheel" before the boat struck the pier, which is one of San Francisco's only public boat launches. KCBS reports, however, that "the boater was trying to motor up to the pier but accidentally hit the throttle slamming the 18-foot boat into the abandoned pier and then spun out of control."

Talmadge told the Chron that the boat in question was a "make-shift plywood vessel," but witnesses tell KCBS that it was actually a vintage, 1959 Dorsett, piloted by "a longtime boater, who liked having big engines in his boats, but didn’t have a kill-switch aboard."

Regardless of those details, by the time SFFD had arrived, all that remained was floating debris and the body of the boat's driver, floating in the water.

By 7:30, the man's body had been retrieved. No one else was injured in the wreck, and San Francisco's Medical Examiner is now working to determine the cause of the boater's death.