Police were conducting a massive manhunt Sunday morning after a police officer was struck, dragged and seriously injured in a hit-and-run in East Flatbush, Brooklyn.

The cop, an Anti-Crime Unit officer from the 67th Precinct whose name was not released, had been responding to reports of gunfire at East 53rd Street and Tilden Avenue just before midnight Saturday.

The stolen car that struck and dragged the cop had three occupants who abandoned it on East 53rd Street near Church Avenue and fled on foot, sources said.

As an NYPD helicopter searched the neighborhood early Sunday, the injured officer was in surgery at Kings County Hospital, sources told The Post.