NORTHAMPTON — Police are investigating the cause of a collision that killed a 77-year-old Northampton man who was struck by a car while walking in the Big Y parking lot off North King Street in Northampton Saturday afternoon, according to the Northwestern district attorney’s office.

The collision took place around 3:30 p.m. Saturday when a vehicle traveling west along the roadway in front of the grocery store struck the man, resulting in his death. The victim was walking with his back to the vehicle along the roadway next to the sidewalk, according to investigators.

The driver of the car, a 61-year-old Northampton woman, remained on scene. Her license was immediately suspended as is required by state law in motor vehicle fatalities under investigation, according to the DA’s office.

The fatality remains under investigation by Northampton Police, State Police detectives assigned to the DA’s office, state troopers with the Crime Scene Services Section and the Collision Analysis and Reconstruction Section. The Office of the Chief Medical Examiner will determine the cause of death.