A passenger was stabbed in the back after getting into a scuffle aboard a subway train in Manhattan early Monday, police said.

The incident took place around midnight on a northbound No. 6 train at the 33rd Street and Park Avenue station.

Investigators said the 36-year-old victim and the suspect got into a fight. It was not immediately known what led to the violence.

At one point during the brawl, the suspect produced an unknown cutting object and stabbed the other man in the back, cops said.

The victim was taken to an area hospital in stable condition. He has not been named.

The suspect fled the subway train and remained on the loose Monday morning, police said.

The male attacker has not been identified so far.