Maine fire marshals are investigating an explosion in Aroostook County that completely destroyed two homes on Shore Road in Sinclair on Saturday. Photo courtesy of Maine State Police

An explosion that destroyed two homes in Aroostook County on Saturday was caused by a disconnected propane line, officials said Thursday.

The Office of State Fire Marshal concluded that the explosion at 441 Shore Road in Sinclair was an accident. The propane line had been disconnected from a heating unit that had been mistakenly turned on, triggering the explosion, Shannon Moss, spokesperson for the Department of Public Safety said in a statement.

Both homes were labeled complete losses after the explosion. Though no one was killed, the resident of the first home escaped with non-life-threatening injuries and was transported to the hospital, where he was treated and released. His neighbor escaped the house uninjured, Moss said.