Brentwood FD was dispatched to a report of a fire in a commercial building at 1948 N. Fehr Way in Baywood at 1222 hours. Units arrived to find fire rolling out of an auto body shop in a multi-occupancy commercial building. Crews stretched on the fire and mutual aid was requested from Bay Shore FD for an engine, West Islip FD for a RIT, Islip to cover at Brentwood FD, Commack to cover at Brentwood FD and Deer Park FD to the scene. East Brentwood FD sent an ambulance along with Brentwood Legion. Multiple lines were stretched and crews extinguished the fire. Suffolk PD Arson is handling the investigation.