A Pennsylvania high school grad was gunned down in a senseless act of road rage — and cops say her killer is still on the loose.

Bianca Nikol Roberson, 18, was driving a green Chevrolet Malibu on Route 100 in West Goshen, Pa., Wednesday afternoon, police told NBC 10. When she went to merge into a lane, a red pickup truck tried to move into the lane at the same time.

Both cars were trying to merge into the part of the highway where it goes from two lanes into one. When both cars were trying to get position, the driver of the pickup truck pulled out a gun and shot Roberson in the head, police said.

Roberson was killed instantly and her car went off the road, crashing into the woods. The driver of the pickup truck fled the scene and continued down the highway.

Chester County District Attorney Tom Hogan said during a press conference the incident is now being looked at a murder case. Authorities are asking anyone with information about the truck or the driver to contact the West Goshen Police Department Traffic Safety Division.