Local media outlets report the crash happened Thursday afternoon on U.S. 17 near Awendaw (Ah-win-DAW) in Charleston County.
Sheriff's Lt. Rita Zelinsky says a pickup made a quick lane change to avoid hitting a slowing vehicle in front of it and sideswiped another pickup truck. The victim's pickup then ran off the road and hit a tree.
The male driver died at the scene. Three men in the truck were taken to a hospital where one of them died.
The names of the victims have not been released.
Those in the other pickup truck were not hurt.
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