Firefighters battled a raging four-alarm Brooklyn fire early this morning, authorities said.

The blaze began about 3:30 a.m. at the three-story Bay Ridge home on 181st Street, near Colonial Road, according to an FDNY spokesman.

It took over 160 firefighters three hours to extinguish the blaze on the second and third floor.

Two of the Bravest suffered minor injuries, and were taken to Lutheran Hospital for treatment, the spokesman said. No civilians were injured, and the fire did not spread to other buildings.

Fire marshals are investigating the cause of the fire, authorities said.