A New York City firefighter has suffered serious injuries after a staircase collapsed during a fire at a Bronx apartment building.

The FDNY says a civilian also was seriously injured as a result of the 3:54 a.m. Thursday fire at 1793 Sedgwick Ave. Neither injury was life-threatening.

Another firefighter and civilian suffered minor injuries.

The third-floor fire was brought under control at 4:43 a.m.