Train derails in Christchurch

It is unclear how the train came off the tracks. Photo / iStock

A train has derailed in Christchurch near Moorhouse Ave and is causing traffic to back up.

It's unclear how the train has come off the tracks, but there are no reports of injuries.

There is heavy congestion on Lincoln Rd and motorists are advised to avoid the area if possible.

Kiwirail has advised the train could take up to three hours to clear.