Four young people were killed on a highway north of New York City when their car drifted from the road, traveled 100 yards on a grassy shoulder then slammed into a bridge abutment and caught fire, police said. The accident occurred at about 5:20 a.m. Sunday on the Sprain Brook Parkway in Greenburgh, about 20 miles north of New York City, said State Police Investigator Joseph Becerra. Sunday evening, police were still investigating what caused the vehicle to veer off the highway, roll over a guardrail, then hit the abutment by an overpass. "We're not ruling anything out at this time," Becerra said. Part of the investigation is to determine if the operator lost control or was going too fast. A woman who passed the scene called police to report a massive car fire, police said. Firefighters put out the flames at about 5:45 a.m. and found all four of the car's occupants dead. Police identified the driver of the rental Volkswagen Golf as 19-year-old Bruno Vaccarezza of Greenwich, Conn. They said 19-year-old Fernanda Gomez of Port Chester, N.Y., was in the front seat. Juliana Restrepo, 18, also of Port Chester, and Vincent Mendoza, 20, of Norwalk, Conn., were in the backseat, police said.