PORTLAND, Maine — Portland’s most senior firefighter has died in an apparent off-duty boating accident in Casco Bay, fire officials said Saturday.

Rescuers with the Portland Fire Department and U.S. Coast Guard were called to the area of Cushing Island at 12:40 p.m. Friday on a report of an unmanned vessel. They found firefighter Timothy Flynn in the water about 500 feet from his boat.

Efforts to revive Flynn on the scene and at later a local hospital were unsuccessful, fire officials said.

Flynn, 58, had been with the Portland Fire Department since 1986 and spent years serving on Ladder Co. 1 out of the Munjoy Hill Station. Later he became pilot of the department’s Marine 1 vessel, a post he held until his death.

He was a lifelong resident of Peaks Island, where he also worked as a firefighter. Portland Fire Chief Keith Gautreau said Flynn was “one of our most respected and beloved firefighters.”

“The tremendous void caused by this tragic loss will be felt for a long time in our Department and with his family and friends on Peaks Island,” Gautreau said in a statement.