A truck and trailer load of paper products burns on the highway.

Flames shot out the side of a truck and trailer unit that burst into flames on the side of a Taupo highway.

There were fears the blaze could spread to a nearby forestry plantation, Northern Fire Communications shift manager Jaron Phillips said.

The B-train truck carrying a double trailer load of mixed goods caught fire on State Highway 1, just south of Taupo, about 11am on Tuesday.

SUPPLIED Flames move through the goods onboard.

Police were forced to close the highway 3km south of Waitahanui village to allow fire services to deal with the blaze.

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Phillips said two fire crews from Taupo and two tankers were dousing the blaze.

MATT SHAND/FAIRFAX NZ The trailer's burnt out skeleton.

Truckie Mark Prujean was enroute to Auckland when he drove into the fire scene.

"The whole thing was going up.

"Whatever is in there is highly combustible as it kept making popping and banging noises."

MARK PRUJEAN Explosions could be heard coming from the truck and trailer that caught fire.

When Prujean arrived, third on the scene, there was one fire truck attending to the blaze.

"They ran out of water reasonably quickly unfortunately and it was well on fire - the tractor units were driven away from the actual trailer units.

"They just couldn't get it so they backed away in the end until they got back up, which took about 20 minutes."



At one stage, flames shot out the side of the trailer, which was stopped on the grass verge.



"There was explosions going off.



"The grass actually caught fire but it was wet enough to dampen it out."



The truck driver was out of the cab and appeared to be okay, he said.

MATT SHAND/FAIRFAX NZ Traffic was backed up on State Highway 1 but one lane is now open.

Traffic had backed up along the highway as far as Prujean could see.

Police encourage motorists heading north to take the SH41/32 junction at Turangi if they want to continue to travel north while the road is closed.

The road is estimated to be closed for an hour from 11.30am.

MARK PRUJEAN The first fire truck ran out of water trying to douse the blaze.

SUPPLIED The view from the cab of a truck at the scene.