One person is dead after a car crashed into a tree just before 7.30am at the intersection of State Highway 7 and Hurunui Bluff Road.
Police and emergency services are attending to the fatal crash in the Hurunui District.
"The Serious Crash Unit is now investigating and for that reason the road has been closed," police said in a statement.
Diversions are being put in place, and police said there could be delays.