The Boerum Place fire escalated quickly. Chopper 4 was over the scene.
Firefighters were battling a raging blaze at a gym in Brooklyn Monday morning that left at least a dozen people injured, authorities said.
The fire at UFC Fit, formerly a New York Sports Club, on Boerum Place by Pacific Street in Boerum Hill was reported around 10 a.m.
It was contained within three and a half hours.
A total of 12 injuries were reported -- three civilians and nine firefighters, according to the fire department -- though the extent of the injuries wasn't immediately clear.
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All three civilians were treated on scene, while the hurt firefighters were taken to area hospitals as a precaution.
More than 200 fire and EMS members were at the scene of the two-story inferno.
The city's Office of Emergency Management tweeted out a message warning people to expect smoke and delays in the area as authorities investigated.
A cause of the fire remains under investigation.
