The NYPD says three subway riders were stabbed and injured overnight in separate incidents.

The first happened at 2:28 a.m. after two suspects boarded a southbound Q train at the Atlantic Avenue station in Brooklyn.

Police say they demanded money from a rider and when he refused they stabbed him in the head and stomach.

The suspects fled when the train pulled into the Prospect Park station. A broken knife was recovered in the station.

About an hour later, two men were stabbed aboard a southbound 4 train at the Lexington and 116th Street station in Manhattan.

Police say both victims were slashed about the face during an argument with two other men.

All the victims were taken to hospitals. None suffered life-threatening injuries.

There were no immediate arrests.

(AP)