Police in Phoenix Thursday were hunting for a group of men they accused of following a driver before shooting her in the head -- apparently while she was calling 911.

Investigators said shortly after the call on Wednesday night, they found a woman critically injured at the scene of a car crash, and she died at a nearby hospital.

The woman who called 911 claimed somebody was driving erratically in a truck and "actually chasing her," Phoenix Police Sgt. Jonathan Howard told Fox 10. He said the dispatcher then heard three gunshots before the call ended.

The car crashed into a center divider on State Route 51, police added.

Based on the woman's description, police said three Hispanic men were in the white truck. Investigators said the vehicle carried ladder racks and a toolbox. A possible motive was unclear.

Four other vehicles crashed after the shooting, Fox 10 reported, adding that paramedics rushed two other people to hospitals with minor injuries.

Police said there was no sign the crime was related to the recent serial shooting case putting the city on edge.

Click for more from Fox 10.