A truck crash has closed a section of State Highway 1 near Cheviot in North Canterbury this morning, leaving two people injured.

Emergency services were called to the scene on Domett Road around 8.10am.

A police spokesperson said it appeared to be a single-vehicle crash involving a truck.

A St John spokesman said a helicopter responded and airlifted two patients, one in minor condition and one in moderate condition, to Christchurch Hospital.

The crash has blocked the highway between Old Main Road and Nonoti Road.

Contractors have been contacted to assist with clearing the scene.

Motorists are advised to avoid the area, expect delays, and use alternative routes if possible.