LANESBOROUGH, Mass. — Police are investigating a one-car accident that killed a 51-year-old New Ashford woman on Thursday night.

Sheryl A. Surprenant of State Road in New Ashford was driving northbound on Route 7 when her car crossed lanes and went off the road, crashing through the sign for the former Lamp Post Motel, on the southbound side, said police.

Officers responded at  9:22 p.m. to the report of a vehicle off the road near the motel on Route 7. The Chrysler had flipped and was lodged in trees and brush.

"The vehicle was on its roof and in the trees. She was pronounced dead on the scene," said Sgt. Gary Kirby on Wednesday. "It was a very difficult extrication by Lanesborough Fire and EMS."

A passerby, who works in the tree removal business, reported the accident and began clearing brush until emergency responders arrived. Speed was a factor based on evidence at the scene and a witness account, according to police, but the rest of the circumstances are still under investigation.

The accident caused some backed up traffic but the road remained open.

Kirby was not on the scene that night but Officers Brad Lepicier and Robert Moore, and Investigator Timothy Sorrell responded along with Lanesborough firefighters, emergency medical services, and County Ambulance. The Massachusetts State Police accident reconstruction team is assisting with the investigation.

Suprenant, a Pittsfield native, resided for many years in Southwick before returning to the area.