WARREN — City firefighters responded Thursday night to a fire at the Grease Monkey, 3880 Mahoning Ave.

The State Fire Marshal is investigating.

A fire department spokesman said the auto-repair business was in flames when crews arrived after 6 p.m. Responders were able to extinguish the fire quickly.

He said the cause of the fire is unknown. There were no reported injuries.

The business is near the border between the city and Warren Township, whose police department assisted with traffic control on Mahoning Avenue.