CANAAN — A lightning strike sparked a fire that caused a barn to collapse at a Canaan home late Wednesday, officials said Thursday.

Firefighters responded to the fully involved structure fire at 46 Hinckley Road, numbered as Route 23, and found the 30-by-40-foot barn “nearly to the point of collapse,” Chief Charles Worcester of the Canaan Fire Department said. The fire was reported around 11 p.m., according to Somerset County’s emergency dispatch log.

“Within five minutes of arrival, the barn had collapsed,” Worcester said.

The home on the property, about 200 feet from the barn, was not damaged, Worcester said.

An investigator from the Office of State Fire Marshal was called to the scene overnight to determine the fire’s cause, the chief said Thursday morning.

“To be honest, it was really hard to tell what it may have been,” Worcester said, noting that the barn had no power.

By Thursday afternoon, investigators determined that the fire was caused by a lightning strike,  Shannon Moss, public information officer for the Maine Department of Public Safety, said.

Thunderstorms were reported in central Maine Wednesday night and Thursday morning.

The Hartland Fire Department assisted Canaan’s firefighters, Worcester said. Other mutual aid departments responding from nearby towns were called off after Worcester saw the barn collapsing from the fire.

“I had struck a second alarm once I saw the glow before I laid eyes on it. Just by the glow, I could tell there was something cooking pretty good there,” he said. “But by the time I got on scene, like I said, it was on the verge of collapse.”

One Canaan firefighter stumbled and was treated for a very minor knee injury, Worcester said. No other injuries were reported.