MODESTO (CBS13) – An off-duty Oakdale Police officer has been identified as the motorist that was killed in an accident on a rural Modesto highway Thursday afternoon that also sent a veteran Caltrans worker to the hospital.

The accident happened as crews were sealing asphalt and had reduced traffic to one lane on Highway 132 near Faust Road west of Modesto. Two cars stopped, but for unknown reasons the semi truck driver behind them didn’t stop and slammed into both cars.

Skid marks show the truck driver eventually did try to stop, according to the CHP.

One driver was killed. The Oakdale Police department confirms the driver was an off-duty officer with their department.

A Caltrans maintenance worker, Brian Smith, who was flagging cars to alert them to the lane closure was hit and suffered major injuries, the CHP said. He was airlifted to a local hospital.

Smith was a 30-year veteran of the department. His family is with him at the hospital.

The CHP said Smith was alert and conscious when responders got on scene.