Three people have been injured in a crash that closed State Highway 1 near Ashburton.
A St John spokesperson said two people were seriously injured and another was in a moderate condition.
A Waka Kotahi NZ Transport Agency spokesperson said traffic was backed up "considerably" after the crash.
A Fire and Emergency NZ spokesman said SH1 was closed after the three-car crash near Wilkin St in Tinwald about 11.30am today.
The spokesman said three people were trapped in one vehicle but had been freed by 12.20pm.
Three ambulances and two helicopters were sent to the scene.
The injured were taken to Ashburton Hospital. From there, the two seriously hurt would be airlifted to Christchurch Hospital.
"Expect delays and please follow the direction of emergency services until this has been resolved."