Han Van Hoang, 43, and 3 year old girl killed in crash in Chelmsford on June 8.

CHELMSFORD, Mass. (WHDH) - Massachusetts State Police are investigating a crash in Chelmsford that resulted in the deaths of a 43-year-old Quincy man and a 3-year-old girl.

Just before 1:00 a.m. Sunday, state troopers responded to a single car crash at a rest area on Route 495.

Preliminary investigation indicated that the vehicle involved in the crash was a 2004 Toyota Camry and was traveling southbound on Route 495 when it veered off the highway and collided with a guardrail, according to State Police.

The victims were identified as Han Van Hoang, 43, of Quincy. The passenger was a 3-year-old girl. The child was reportedly belted into a car seat.

There were no road closures. Crews worked to replaced the mangled guardrail.

The investigation is still ongoing, trying to figure out how the driver lost control of the vehicle.