Three people, including a young child, died on the N12 between Emalahleni and Delmas, in Mpumalanga, on Thursday morning.
Provincial department of safety and security spokesperson Moeti Mmusi said a fourth person was seriously injured.
"The collisions are believed to have been caused mainly by misty conditions on that road."
The road has since been closed.
Motorists have been advised to use alternative routes or the R555 road between Ogies and Emalahleni to travel to and from Delmas.
WATCH | Young child among 3 killed in N12 multiple vehicle crash
Three people, including a young child, died on the N12 between Emalahleni and Delmas, in Mpumalanga, on Thursday morning.
Provincial department of safety and security spokesperson Moeti Mmusi said a fourth person was seriously injured.
"The collisions are believed to have been caused mainly by misty conditions on that road."
The road has since been closed.
Motorists have been advised to use alternative routes or the R555 road between Ogies and Emalahleni to travel to and from Delmas.