Firefighters responded to a two-alarm apartment building fire in Williamsburg early Thursday morning.

Citizen app video shows flames filling up one window of the 60 Mott St. building. Officials say they responded to a call at 1:45 a.m. and after arriving to the scene, they tended to flames coming from the third floor of the building.

The video also shows FDNY members fighting the flames to rescue a child in the burning building. The child was pulled from the building but is currently in critical condition.

11 people, including two firefighters, are suffering from minor injuries. Six of them were transported to area hospitals. 

The cause of the fire is still being investigated.