Authorities believe that was cut off by a passenger car.
According to the Massachusetts State Police, in an attempt to exit off of Route 128 South, the car moved quickly from the second travel lane into the rightmost lane, close to the tanker.
The car was believed to be slowing down to exit the highway, and the tanker truck was unable to stop, said authorities.
"[The tanker] struck the passenger car, swerved and rolled over," said a MSP spokesman late Tuesday night.For up-to-the minute updates on this story and others, follow Woburn Patch on Facebook and Twitter, or sign-up for our e-mail newsletter.
The driver of the tanker, Michael Cormier, 50, of Waltham, was transported to Massachusetts General Hospital by Woburn Fire with non-life threatening injuries. The truck is owned by Liberty Transport of Quincy.
The car's driver, Jane Lindsay, 53, of Dorchester, was transported by Woburn Fire to Winchester Hospital, also with non-life threatening injuries.
The tanker spilled almost 10,000 gallons of gas onto Route 128, causing the highway to be shut down in both directions while Woburn Fire and area fire departments, as well as hazmat cleanup crews, tended to the scene. The
According to the MSP, the crash is still being investigated.
"Charges may be forthcoming; Any charges, if filed, will be done at the conclusion of the investigation," said the state police.