The highway had been closed at the Connecticut border after a woman was struck and killed on the highway by a truck, police said.
Massachusetts state police said the incident occurred about 2:30 a.m. Troopers from the Springfield barracks responded to a report of a person hit and found the young woman dead. Preliminary investigation suggests she was on foot when struck, but may have been a passenger in a car some time prior to the crash.
Police said their investigation is continuing. They did not identify the woman.