Cops are looking for a “person of interest” in the Friday night stabbing outside a Brooklyn gambling den that left a good Samaritan dead, police sources said Sunday.

The person sought for questioning in the 9:30 p.m. stabbing at 57th Street and Seventh Avenue in Sunset Park drives a white Mercedes Benz, sources told The Post.

A 46-year-old good Samaritan died trying to intervene in the knife fight outside the illegal gambling spot in Brooklyn’s Chinatown.

Three other people were wounded and are being treated at area hospitals, sources said.

The melee started when three men tried to break into the building but were stabbed by an employee before they got inside, sources said.

The neighborhood is known as “Little Fuzhou” after a city in China’s Fujian province, where many local residents hail from.