Traffic crossing the Kaimais on State Highway 29 this morning encountered delays caused by two truck breakdowns.

The first was at about 7am when the driver noticed his trailer was on fire.

The first truck to encounter difficulties on the Kaimais.

He pulled over and parked the trailer, a tanker, on the side of the road.

The fire in insulation over the rear wheels was extinguished by Greerton fire fighters.

Police at the scene say the trailer, which usually carries tallow, was empty and the trailer had recently been worked on.

The truck and trailer stopped on the side of a two lane section, blocking one lane. Drivers on the scene delayed their own journeys while they directed traffic.

The second truck to encounter difficulties on the Kaimais.

The tow truck had arrived to take the trailer away when a second truck and trailer unit was forced to stop on the side of the road just 200 metres past the first breakdown.

This breakdown was a mechanical fault.

The highway is expected to be cleared by mid morning.