Robert Bibeau, 80, died today due to injuries sustained in an accident yesterday on Route 128. His wife, Joan Bibeau, 77, died yesterday afternoon.

State police responded shortly after 3:30 p.m. Monday to the single-car crash on Rte. 128 northbound near Route 9 in Wellesley.

A preliminary investigation by Massachusetts State Police shows that a 1997 Dodge van was traveling northbound in the left lane when it veered to the left side of the road. The van then struck the guardrail and hit the bridge abutment.

Robert Bibeau was driving the van and was transported via helicopter, where he died earlier today. Joan Bibeau was sitting in the passenger side of the van and was pronounced dead upon arrival.

The State Police, along with the State Police Collision Analysis and Reconstruction Section and the State Police Crime Scene Services Section are currently investigating the cause of the accident.