A police officer in Brooklyn suffered a heart attack and died Tuesday morning on the NYPD training grounds, sources said.

Officer Juan Feliciano was on-duty when he went into cardiac arrest inside Floyd Bennett Field around 9:30 a.m., officials said. A police source said he was dropping off his bike to be repaired.

Feliciano was unresponsive when EMS arrived and rushed him to Coney Island Hospital. He was pronounced dead at 10:53 a.m., sources said.