Stonington – Tuesday evening’s Moss Street fire is under investigation as incendiary and police believe a group of juveniles may have started the blaze.

The two-story, barn-like structure was demolished after the 4:42 p.m. fire because the roof collapsed and it was unstable, Pawcatuck Fire Marshal Kevin Burns said. How the blaze began remains under investigation, said Capt. Jerry Desmond of the Stonington Police Department, but it appears to have been set by a group of juveniles who were in the area at the time. One child suffered minor burns from the fire, Desmond said, but was treated on scene and didn’t require hospital care.

“No one has been charged yet but we are investigating,” Desmond said Wednesday.

Burns, the fire marshal, said the three bay garage serves as storage space for the tenants of 26 Moss St., which he said is a three-family residence. Accelerants were not found but Burns said a boat and gas cans were inside the structure.

“The boat was not damaged but there was plenty of other fuel in there to keep the fire going,” he said.

The fire was under control in about 30 minutes, Burns said.