Toxic truck inferno closes State Highway 7 in South Island

Lewis Pass is closed at SH7 Hanmer Springs and at Springs Junction. Photo: Google Maps

A truck carrying toxic chemicals has caught fire on the Lewis Pass Rd (SH7), closing the road to all traffic.

Fire engines from Hanmer Springs and Christchurch were sent to the fire near the Engineers Camp on Lewis Pass Rd (SH7), about 22km south of Lewis Pass, at 8.20am.

The road, which is known as the alternative South Island state highway, has been in heavy use since the November earthquake damaged the coastal State Highway 1 route.

Crews from Christchurch included a hazardous materials team, equipped to deal with toxic spills.

A fire communications spokesman could not confirm what chemicals the truck was carrying, but said the road will be closed for "some time".

"We have no reports of casualties or injuries at this point," he said.

The road had only reopened on Thursday after it was closed because of heavy snow on Wednesday.

Road blocks are in place at the Hanmer Springs turn-off and at Springs Junction, a police spokesman said.

"There are no diversions available and motorists are asked to delay travel in the area," he said.