A serious multi vehicle crash has closed State Highway 6 on the West Coast this afternoon.

Police said they were called to the collision near Donoghues Road between Kakapotahi and Ross at 1:10pm. Initial indicators are there have been serious injuries.

Two helicopters from Christchurch and one from Greymouth have been called to the scene.

A police spokesperson said the Serious Crash Unit has been advised and the highway is expected to remain closed for some time while emergency services work at the scene.

Motorists are being urged to avoid the area and to expect significant delays.