WESTPORT — A Stamford woman was killed Wednesday night when her car veered off the Merritt Parkway and rolled onto its roof near exit 41.

State Police have identified the woman as 51-year-old Lisa C. Brown, of Main Street. Brown was pronounced dead at the hospital.

Her passenger, identified as 40-year-old Donell Terrence Alston, was treated at Norwalk Hospital for non-life threatening injuries, the State Police said.

According to Trooper Clinton C. DeSoto's accident report, Brown was driving northbound shortly after 10 p.m. when her 2004 Lexus GS 300 left the roadway near Twin Oaks Lane, which is about a quarter of a mile before exit 41.

DeSoto said the Lexus struck a tree and then rolled over onto its roof. The Norwalk Fire Department on-scene commander reported when he arrived at the scene that one person was trapped inside the car and another person was on the ground. He said the car was overturned and about 40 feet into the woods.

The accident remains under investigation. State Police ask anyone who witnessed the accident to contact Trooper DeSoto at 203-696-2500.