Two people are in a critical condition and eight others are suffering from varying injuries following a crash involving multiple vehicles near Oamaru.
Police rushed to the scene on State Highway 1 at Maheno around 6pm to find people trapped in the vehicles involved.
At least three helicopters were sent to the incident.
Initial reports from police said five people were injured in the crash, later correcting that number to nine. However St John Ambulance confirmed 10 people had sustained injuries in the collision.
Police also said it appeared two vehicles were involved - one containing three people and the other six.
Nine ambulances attended the incident and treated patients. The injured people were then transported to Dunedin Hospital.
Two people were in a critical condition following the crash, St John said. Four others were in a serious condition and four had moderate injuries.
At 10.30pm police were still at the scene. One lane is now open and traffic is flowing, police said in a statement.
The Serious Crash Unit is attending and there may be road closures later tonight while the scene is examined, police said.
Northbound traffic was earlier being diverted at the intersection of Fortification Rd and SH1. Southbound traffic was also being diverted, at the intersection of Happy Valley Rd and SH1.