MONMOUTH — Fire destroyed a barn and its contents at an unoccupied property early Tuesday.

The Office of State Fire Marshal is investigating the cause of the fire at 179 Tillson Road, owned by Wayne Ward.

The property, which included the barn and a mobile home about 50 feet away, was unoccupied and did not have electricity connected, Monmouth fire Chief Dan Roy said.

Roy said the roughly 20-by-30-foot barn was fully involved in flames when he and other firefighters arrived, and it had already collapsed to the ground.

About a dozen Monmouth firefighters had the flames out and were on the scene for about 30 minutes, after responding to the 5:18 a.m. report of a structure fire.

Roy said the barn was being used for storage of tools and household items. He said the property has been vacant for several years.

“The whole building, and contents, were destroyed in the fire,” Roy said Wednesday. “There was no power to the building. We brought the state fire marshal in for an investigation.”

Shannon Moss, public information officer for the state Department of Public Safety, confirmed the Office of State Fire Marshal is investigating. She said Wednesday investigators have deemed it an accidental fire, but the cause was still under investigation.

Roy said a call for mutual aid was canceled as the fire had already destroyed the barn and was contained to that structure with the mobile home undamaged, so additional firefighters weren’t needed.

“It was a quick knockdown of the fire, and it was surrounded by snow and not going anywhere,” Roy said of the fire.

A neighbor reported the fire.