NEW YORK (CBSNewYork/AP) – Thirty one people are injured—four of them critically—after a fire ripped through an apartment building in the Sunset Park section of Brooklyn on Sunday morning.

New York City Fire Department press officer Chris Korzekwinski says firefighters received the call at 5:12 a.m. for a blaze at 510 61st St.

LISTEN: 1010 WINS’ Kathleen Maloney reports on the fire

As soon as firefighters arrived, Deputy Chief Richard How said they got right to work, rescuing everyone as the smoke consumed the building.

“There were people on all parts of the fire escape being removed,” How said.

In addition to the four people in critical condition, four others are listed as serious.

Investigators said they put the fire under control by 7:27 a.m.

One firefighter suffered a minor injury.

The cause remains unknown as the investigation continues.

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