Virginia State Police say a father and son have died after being hit by a tractor-trailer while trying to help driver who wrecked in snow on Interstate 81.

Around 12:40 a.m. Friday, a car spun out of control on I-81 in Wythe County and one of the passengers was injured. The men stopped to help, and minutes later a tractor-trailer trying to avoid the vehicle jackknifed, striking their minivan.

Police say 25-year-old William Edward Smith Jr. of Mooresburg, Tennessee, was standing outside the minivan and was struck. His father, 54-year-old William Edward Smith Sr. of Sylva., North Carolina, was inside the minivan. Both died at the scene.

A third occupant of the minivan, a nurse who was helping the person injured in the car, was not injured.

State police are investigating and say charges are pending.

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