Six people are dead and nine others, including five first responders, were injured after a fast-moving, three-alarm fire tore through a two-story row house in Brooklyn early Thursday, New York officials said.

The blaze broke out in a home on 58th Street in the Sunset Park neighborhood shortly before 2 a.m. ET, the New York Fire Department reported, and was raised to three alarms by 2:10 a.m. More than 200 first responders rushed to the scene, and the fire was brought under control just before 4:30 a.m.

Four residents were pronounced dead at the scene, and two others died after being taken to local hospitals, officials said. All six of the people killed were adults, and their names had not been released. Firefighters rescued four people from the building, including two who were trapped behind window bars and reached through a rear entrance.

Four civilians suffered injuries, and three firefighters and two police officers responding to the call suffered minor, non-life-threatening injuries. All nine injured people were expected to survive.

FDNY Chief of Operations Kevin Woods said crews were met with "fire on every floor," with flames blowing out every window and bursting out of the front door. The cause and origin of the fire remained under investigation Thursday, officials said. A lithium-ion battery was found at the scene, but it was unknown whether it was related to the cause of the fire.

Mayor Zohran Mamdani confirmed the death toll at a morning news conference and said the city would support the families affected. The home, built in 1915, was one of a block of 25 wood-frame homes in the densely populated, working-class neighborhood.