A boat exploded last night at the John Wayne Marina in Sequim, Washington, seriously injuring a man on board.

The 40-foot boat blew up about 5:45 last night at the “C” dock in the marina.

Fire District Three spokesman Patrick Young says the explosion was so large, boats within 75 yards were also damaged. One couple on a boat two slips away was knocked down due to the force. An unidentified 78-year-old man was in the hull of the boat which exploded, covered in debris. He was removed from the water and taken to Olympic Medical Center with serious burns.

Fire and Coast Guard crews spent the night containing spilled fuel and oil that came after the boat sank.

The cause of the explosion is still under investigation.