Picton fire chief Wayne Wytenburg is praising his firefighters' quick thinking as they tackled a truck trailer fire near Koromiko in the early hours of Saturday morning.

Picton fire station officers Jason McMillan and Raymond McKay were sprayed with water as they crawled under the burning trailer to free it from the truck unit.

After they freed the trailer, the truck driver was able to shift the truck unit to a safe position further up the road.

The situation would have been a lot worse had the fire spread to the truck's engine, Mr Wytenburg said.

The driver of the truck-and-trailer unit escaped unhurt.

"Everyone did a bloody good job," Mr Wytenburg said.

"The truck is largely undamaged thanks to a particularly good team effort."

The fire started in the trailer, which was loaded with jam, chocolate and kiln-dried timber.

Firefighters had to reconsider their options after struggling to put the fire out because of the large amount of freight on the trailer and the limited supply of water in the area.

One of the firefighters, Koromiko farmer Ian Taylor, used his tractor to push the burning freight off the trailer so the fire could be brought under control.

Two Picton fire engines, and two 5000-litre water tankers from Blenheim attended the fire, which took nearly three hours to put out.

Blenheim police were brought in to control traffic and State Highway 1 was closed for a short period as water was pumped from a ditch on the other side of the road.

An electrical fault in the trailer's refrigeration unit is believed to have sparked the fire, but that was yet to be determined, Mr Wytenburg said.

It was not known where the driver was from, but the truck was believed to have Toll New Zealand signage.

Toll New Zealand could not be reached for comment yesterday.

- The Marlborough Express

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