A raging 4-alarm fire in the Bronx ripped through the upper floors of an apartment building Sunday, injuring four people – including two firefighters — and displacing dozens of bewildered residents five days before Christmas, the FDNY said.

It began on the fifth floor of a building on Clay Ave. near E. 173rd St. in Claremont around 5 a.m. and quickly spread to other apartments and the cockloft, officials said.

About 170 firefighters responded to the fire, which was brought under control about two hours later.

Those whose apartments were destroyed by fire or smoke damage, stood outside Sunday afternoon, gaping at the loss.

“There’s kids that have to go to school tomorrow. This is a catastrophe to them,” said Jahaira Rijos, 33, who said once she didn’t have time to rescue her belongings.

“Christmas is in five days and [many residents] lost everything.

Although the cause of the fire is still under investigation, residents say there’s been lingering issues with the gas lines.

Princess Barrett, 32, said she got her family out in the nick of time.

“Under the sink, that’s where all the smoke was coming. My daughter screamed, ‘Mommy, the house is fogging up’.”

“I don’t know what I’m gonna do. We lost everything.”