A single-vehicle accident on Interstate 495 South at the Chelmsford rest area killed the man driving the vehicle and a girl who was his passenger.
The crash happened about 12:50 a.m. State police said a preliminary investigation indicated the vehicle hit a guardrail.
The names, ages, and hometown of the victims were not released pending notification of next of kin.
The crash was confined to the rest area and did not require highway lane closures.
The crash is under investigation by Troop A of the Massachusetts State Police with the assistance of the State Police Collision Analysis and Reconstruction Section and Crime Scene Services Section.