Witnesses said the violence near 135th Ave. and 243rd St., Rosedale, broke out about 8 p.m., apparently over how extras were being hired for scenes to be filmed tomorrow.

The victims, three men aged 26, 24, and 23, were taken to North Shore University and Mary Immaculate hospitals, two stabbed in the stomach and one stabbed in the back, cops said. All were in critical condition.

Investigators were trying to piece together what happened but had few details last night.

Witnesses said shots were fired during the fracas. Crime scene cops later combed over a car with a blown-out window.

One witness said "production people and scouts" arrived a couple of hours before the fight. He said they wanted extras for a sequel to the 1998 gangsta rap epic "Belly," directed by Hollis, Queens-born Hype Williams about two holdup men, played by rappers DMX and Nas. The film production company did not return calls.

Patrice Kristaghay, 16, said "some guys from around here were talking with the movie people, then it got loud and then there was a fistfight."

Suddenly, she said, the yelling got louder, and "I saw a guy on the sidewalk bleeding. It was gushing out so fast I had to put my shirt over [the wound]."

Porchia Keeley, 35, said she was sweeping her sidewalk when she heard shots. "I was terrified," she said. "I thought I was going to get shot. Then this young black man in a camouflage suit came running toward me holding his stomach.

"He was bleeding so I told him to sit down and I went to call an ambulance. There was a lot of blood on the ground," she said.