HEATH — Autumn Walsh, 20, of Buckland died in a car crash on Dell Road Sunday night. Two other people in the car were treated for serious injuries, according to Massachusetts State Police.

A Toyota Camry crashed head-on into a tree around 7:45 p.m. When police arrived, all three people in the car were found out of the car.

Walsh was pronounced dead at the scene. The other two, a 21-year-old woman from Colrain and a 28-year-old man from Hinsdale, N.H., were brought to Baystate Medical Center in Springfield for treatment of serious injuries.

The reason for the crash remains under investigation. Also, investigators are trying to determine who was driving the car. Called in were the State Police Collision Analysis and Reconstruction Section, Crime Scene Services Section, and troopers assigned to the Northwestern District Attorney’s Office.

In addition to state police, Colrain and Charlemont EMS and firefighters responded.

As of Monday afternoon, the cause of the accident remained under investigation.