The fire chief says the dock lines securing that boat burned off, and the burning vessel then drifted and caused another boat and two docks to catch fire.

The man, his 16-year-old son and a friend, 15, were at the boat launch near Highland Road and Williams Lake Road, preparing to take a 17-foot Chris-Craft boat onto Pontiac Lake when the explosion happened.

One person was injured when a boat exploded on Sebago Lake on Tuesday and set a second boat on fire. The incident began Tuesday evening in the Turtle Cove area when a boat exploded, injuring one person who was aboard, Naples assistant fire chief Jeff Lake said. A unoccupied boat that was tied to a nearby dock then caught fire, he said.