Four people have been injured in a serious crash involving four vehicles near Tekapo.

A police spokesperson said emergency services were called to State Highway 8 west of Tekapo at 7PM.

The crash happened between Tekapo Powerhouse Road and Braemar Road.

Three people have been seriously injured, while another has moderate injuries, the police spokesperson said.

Three rescue helicopters responded to the crash.

The highway is expected to be closed for some time.

Police are asking motorists to postpone travel between Tekapo and Twizel if possible, or expect delays.