A person is understood to be seriously injured in a crash involving two cars near the small Canterbury township of Hinds.
A person was understood to be trapped in the car and fire crews were now working to extricate them.
Two fire crews from Ashburton, and one crew from Hinds are attending the scene.
A helicopter was dispatched to the crash site at the intersection of Coldstream and Junction Rds, near State Highway 1, at 10am.
Initial indications are one person received serious injuries, police said.
