A key Christchurch intersection has been closed following a serious early morning crash.

A police spokeswoman told chrislynchmedia.com the crash at the intersection of Papanui Road and Innes Road happened at 4.15AM and involved a truck and a car.

One person from the car sustained serious injuries, and another person suffered moderate injuries.

The truck driver was uninjured, the spokeswoman said.

The intersection remained closed at 8AM while the Serious Crash Unit completed a scene examination.