Emergency services are responding to a crash on Twizel-Omarama Road, Waitaki.
The two-vehicle crash occurred about 10:19am.
A police spokesman said indications suggest there are injuries.
Chris Lynch Media understand occupants in the two separate vehicles were trapped.
A St John spokeswoman said St John was notified of a motor vehicle incident on Twizel-Omarama Road in Omarama at 1019am.
“We currently have a first response unit, a prime doctor and an ambulance on scene and other vehicles on the way.”
The road is currently blocked. Motorists are advised to avoid the area and expect delays.