BROOKLYN - Cops are searching for the gunman behind a fatal overnight shooting in Flatbush.

According to police, a black man in his 50s was shot in the chest on Flatbush Avenue, near Cortelyou Road, at around 1 a.m. He was rushed to Kings County Hospital and pronounced dead on arrival.

Investigators say it's still unclear what led up to the shooting, and no arrests have been made.

The victim's name has not been released.