The truck was returning from a call and heading eastbound on Broad Street when the collision happened around 7:20 a.m., according to police and the Fire Department.
Firefighters gave the boy aid until an ambulance arrived and took him to a hospital, police said. They are investigating the collision.
Police say it appears the child was trying to cross the street.
Deli worker Felix Rodriguez told the Daily News the boy stepped into the roadway as the truck approached.
"It wasn’t a hard impact, but the fire truck hit him and knocked him back," said Rodriguez, 60. He said the child "was crying on the ground in shock, couldn’t talk."
Rodriguez and other witnesses told media outlets that the fire truck's driver wept after the collision.
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