Waikato Expressway southbound lanes closed with truck in flames

Fire and Emergency NZ was called at 5.57am after a large truck and trailer unit caught fire 3km south of Rangiriri. Photo / Google

A truck fire has closed the southbound lanes on the Waikato Expressway just south of Rangiriri.

Fire and Emergency NZ said it was called at 5.57am after a large truck and trailer unit caught fire 3km south of Rangiriri.

The driver was unhurt and the cause of the fire is unknown, but police said at 7.20am that it was likely to take one to two hours to clear the southbound lanes.

Diversions are in place.

A truck on fire near the Rangiriri Tavern (above) is blocking southbound lanes on the Waikato Expressway. Photo / File

A witness, Wayne Stockman, said there did not appear to be any other vehicles involved and the truck had pulled over to the side of the road. The truck was "fully engaged in flames".

"The whole truck was up in flame," he said.

"I could see it from a distance away, for sure. I would have been 300 metres away.

"It blocked the road off. The only way around was to go back the one-way into Rangiriri and take the river bridge."

Fire and Emergency NZ said the truck was carrying general freight, not fuel, but it would take time to put the fire out because of the size of the truck and trailer unit.

Four fire engines are fighting the blaze.