Ikamatua fire chief Darryl Lawson said it appeared the fully-laden milk tanker had run over the mattress which had been lost on the road.
"The mattress became stuck under the rear axle of the trailer unit and was dragged down the road, creating heat and sparks which in turn caught fire, right under the (truck's) diff."
The driver, noticing a lot of flames coming from the rear, slowed up as best he could but still in the middle of the south bound lane, because the brakes had been damaged by the flames.
Local firefighters were holding their weekly training session at the time so were on hand almost immediately.
The rear-end of the milk tanker was destroyed, and, while some milk leaked, "it wasn't much".
The Reefton brigade was called as a back-up.
Mr Lawson said it was a timely reminder for people to secure their loads, such as furniture.
"A number of the firefighters thought a trailer had been driven past earlier and we had a funny feeling they may have come back looking for it (the wayward mattress).
"The road was blocked until the wreckage was cleared. The brigade was on site for a couple of hours securing the scene, and the road was reopened to one lane before they left. No one was injured. As for the mattress, "just the springs were left".
Contractors were on site this morning repairing the road.
- Meg Fulford
