Seattle police recovered a body in Lake Washington north of the mid-span of Interstate 90, after a witness reported a man clinging to a buoy in the water on Tuesday.

The witness’ report prompted Seattle’s harbor unit to respond to the freshwater rescue, said SPD Detective Patrick Michaud. The Seattle Fire Department, Coast Guard, State Patrol and the Seattle and Mercer Island police departments worked to rescue the man around 4 p.m. Tuesday.

However, by the time units arrived, the man had flipped below the surface and drowned.

SPD was able to recover the body, which is now in the custody of the King County Medical Examiner’s Office. The medical examiner will work to identify the victim and should have a report in two or three days, Michaud said.

“At that point we’ll be able to figure out, hopefully, why he was in the water in the first place,” Michaud said.