Twenty-one firefighters have been taken to hospitals after a blaze tore through a Harlem apartment building Saturday, the fire department said.

None of the injuries is considered life-threatening, and all the patients are in stable condition, the department said.

Firefighters were called around 7 a.m. to a building on West 115th Street and found the blaze on the first floor. It soon surged all the way to the top floor of the six-story building, Chief of Fire Operations Thomas Richardson told the Daily News.

Nearly 170 firefighters were called to tackle the blaze, which took them about 2 1/2 hours to get under control.

It wasn’t immediately clear how many residents were displaced on a morning when temperatures were in the teens.

The cause of the fire is under investigation.

(AP)