Bellevue police and the King County medical examiner are responding to the report of a body floating in Phantom Lake.
Police say it is unclear if it is related to the missing person case in late June, when a farther disappeared after a raft capsized.
Crews pulled a 5-year-old boy from the water the night of June 20, but his 37-year-old father was not found.
The boy had a life jacket on and swam towards firefighters, who then pulled him from the water. The boy was taken to the hospital to be checked out.
Authorities said the boy and his father were on the lake fishing when something went wrong and their raft capsized.
His father was not wearing a life jacket.
"Just a few feet below the surface, there's a temperature change, and had our boater gone to that depth, it could have put him in cold water shock," said Bellevue Police Officer Tory Mangione in June.