BOSTON (CBS) – State police have identified the person who was killed after leaving a moving car on Route 290 in Auburn Monday evening.

Fifty-one-year-old Catherine Berthiaume of Shrewsbury was driving a Toyota Camry eastbound around 5 p.m. when, investigators say, she suddenly left the car while it was in motion.

She hit the road and was then struck by a tractor-trailer. She died at the scene.

The eastbound side of the highway was closed completely for more than an hour after the incident and did not open completely until 8:20 p.m.

Police say they have yet to determine why Berthiaume left the car.