The FDNY worked Thursday evening to make sure a six-alarm blaze at a Sunset Park building was fully extinguished – more than 24 hours after it was first sparked.

The building at the corner of 44th Street and Seventh Avenue was heavily damaged by the fire, first reported around 4:30 p.m. Wednesday. The roof collapsed inside and the sixth floor of the building was left in ruins. The floors underneath suffered significant fire and water damage. 

MORE: FDNY: 23 injured in 6-alarm Sunset Park fire

High winds caused the fire to spread rapidly to another part of the building, and caused pockets of fire to flare up overnight. Its cause is not yet known. 

Officials told News 12 that there were more than 50 families living in the building – many of them immigrants with children and senior citizens. The Red Cross was helping those families at a nearby recreational center. Officials say it will be a while before anyone is allowed in the building for safety reasons.

Fire officials say 23 people were injured, including 19 firefighters. They are all expected to be OK.

The Sunset Park Business Improvement District set up a GoFundMe page to help those displaced. It has already reached $19,000.