Ten people are injured, two critically, after a pile-up on State Highway 1 at Maheno, near Oamaru.
Police said multiple vehicles crashed there about 6pm on Sunday and people were trapped in the wreckage.
Three helicopters were sent to the scene, police said.
St John ambulance says ten people are being taken to Dunedin, two are critically injured, four are seriously injured and the rest have moderate injuries.
It sent nine vehicles to the scene.
North bound traffic will be diverted at the intersection of Fortification Road and SH1.
Southbound traffic will be diverted at the intersection of Happy Valley Road and SH1.