A helicopter has crashed onto a golf course in rural Canterbury, injuring all four people on board.

Three people with serious injuries were flown by rescue helicopter to Christchurch Hospital, and a fourth person, who has moderate injuries, was taken to the same hospital by ambulance, a St John spokeswoman said.
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The crash happened in Windwhistle, 80km west of Christchurch, and was reported to police at 3.05pm.