An 18-month-old Calais boy was burned over 60 percent of his body when his father poured a flammable liquid on a campfire and it spilled.

Wyatt Chandler is being treated for the burns at Massachusetts General Hospital in Boston following the Wednesday incident at his home.

The State Fire Marshal’s Office said Chandler was with his parents in his backyard near a campfire, and the group planned on cooking hot dogs and making s’mores over the flames.

To intensify the fire, Chandler’s father, Joshua Barnard, poured a flammable liquid onto the fire from a plastic bottle, police said. The flames burned back up the liquid stream, igniting the bottle’s contents and causing Barnard to drop the bottle, which spilled the liquid over his son.

The boy was flown via LifeFlight to Bangor and then to Boston for treatment.

The State Fire Marshal’s Office advises never to pour flammable liquid into an open fire.