Firefighters hose down hot spots Monday morning at 138 Mount Auburn Ave. in Auburn after a four-alarm fire late Sunday night destroyed a 50-unit apartment building under construction. Russ Dillingham/Sun Journal

Firefighters hose down hot spots Monday morning at 138 Mount Auburn Ave. in Auburn after a four-alarm fire late Sunday night destroyed a 50-unit apartment building under construction. Firefighters were able to protect a second apartment building almost completed adjacent to the burned building. Russ Dillingham/Sun Journal

Firefighters hose down hot spots Monday morning at 138 Mount Auburn Ave. in Auburn after a four-alarm fire late Sunday night destroyed a 50-unit apartment building under construction. Firefighters were able to protect a second apartment building almost completed adjacent to the burned building. Russ Dillingham/Sun Journal

Firefighters hose down hot spots Monday morning at 138 Mount Auburn Ave. in Auburn after a four-alarm fire late Sunday night destroyed a 50-unit apartment building under construction. Firefighters were able to protect a second apartment building almost completed next to the burned building as well as the BJ’s Wholesale Club building and gas pumps on the opposite side of the fire scene. Russ Dillingham/Sun Journal