A 29-year-old man was fatally shot in the head during an argument with two men inside the basement of a Bronx restaurant early Thursday, police said.

The victim was killed in the basement of M Lounge Restaurant on Jerome Ave. near E. 184th St. in Fordham about 4:30 a.m., cops said. His name was not immediately released.

He was found dead outside the restaurant by responding officers. It was not clear if he had stumbled out of the building after being shot or if his killers dumped him on the sidewalk, cops said.

The men he was arguing with ran off and have not been caught. It was not immediately clear if the victim was shot by both men or one of them, cops said.

One suspect was wearing all black and black sunglasses, while the other was wearing a green shirt with white lettering and black-and- white sneakers, cops said.

Cops are scouring the area for surveillance footage in an effort to determine the identity of the suspects and where they fled to.