MINNEAPOLIS (WCCO) – More than 30 firefighters battled flames for hours Thursday at a Bemidji multi-business building that sustained an estimated $410,000 in damage, the Bemidji Fire Department said.

Motorists reported the fire, which burned in the 3400 block of Bemidji Avenue North, to authorities just before 11 a.m., the fire department said. When crews arrived on the scene, they found smoke rising from the roof. Inside, they found “extensive” fire that they were able to confine to the business of origin, which was not named.

No one was in the business when the fire started, the department said.

Blackduck and Cass Lake fire crews helped the 30 Bemidji firefighters on the scene. Three fire engines and a large track excavator also helped knock down the flames in a fight that lasted about eight hours.

The Bemidji Fire Department, Minnesota State Fire Marshal’s Office and Bemidji Police Department are investigating the cause of the fire.