By Samantha Allen


CHELMSFORD -- Police continue to investigate the cause of a fatal single-car crash on Interstate 495 early Sunday morning that instantly killed a 43-year-old Quincy man and a 3-year-old girl.

Massachusetts State Police said that at about 1 a.m., a 2004 Toyota Camry headed south on I-495, for reasons unknown as of Sunday night, veered to the right and crossed over a raised island that separates the highway from the entrance to the Chelmsford rest area there. The vehicle continued through the grass and then struck a metal guardrail.

The impact killed Han Van Hoang, 43, of Quincy, and a 3-year-old girl who was belted into a child safety seat, according to state police. State police did not identify the 3-year-old or release her relation to Hoang.

The crash remains 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.

The crash was confined to the rest area and did not cause any highway lane closures early Sunday morning. By late Sunday morning, the heavily damaged guardrail had been replaced. Scraps of metal and glass remained at the rest-area site.

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