It happened at 8:15 p.m. at Fourth Avenue and Sackett Street.
Police said a 24-year-old man riding a bicycle was struck by an FDNY vehicle that was on its way to an emergency.
The victim was taken to NewYork-Presbyterian Brooklyn Methodist Hospital where he was pronounced dead.
The vehicle remained on the scene.
A source told Eyewitness News that an EMS vehicle was responding to a call for a baby choking when the crash happened.
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