At least two people are dead after a mixed-use three-story building in New York City, US, collapsed Wednesday afternoon.

Axar.az reports, citing CNN, that there are 19 victims so far, including the two fatalities, four people in critical condition and 12 that are stable, fire officials said Wednesday night.

At least seven of the 19 victims are children.

Rescue workers don’t have a full account of how many people may be trapped or missing, a New York Police Department official said.

The building collapsed around 4 p.m. in the central Brooklyn neighborhood of Flatbush. Video from the scene showed firefighters pulling out several people from a mountain of debris, placing them on stretchers and carrying them up ladders to remove them from the site.

Fire officials remain concerned about a secondary collapse as the rescue operation has stretched past four hours. The building collapsed into an adjacent construction site, trapping multiple people in both. The massive search and rescue operations have been “extremely dangerous,” the New York City Fire Department commissioner said.