A southwestern Michigan barn fire killed 90,000 hens and caused about $2 million in damage, authorities said.

About 120 firefighters from 19 departments responded to the Sunday morning blaze, The Grand Rapids Press reported. Their efforts were hampered by winds gusting up to 40 mph that fanned the flames.

Overisel Township Fire Chief Ron Horsting said the cause wasn't immediately known. Firefighters were able to keep the fire from spreading to adjacent chicken barns only feet from the burning building.

"The biggest problem was the wind and the extremely dry conditions," Horsting said.

Farm owner Cal Schipper, who has about 1 million chickens, said he was grateful the fire did not spread to any of the other seven barns. The farm is located 24 miles southwest of Grand Rapids and about 150 miles west of Detroit.

He said the barn and chickens were insured.