UPDATED 7.30PM: State Highway 2 between Tauranga and Katikati has now reopened after a car towing a caravan crashed into a ditch bringing down power lines and causing the vehicle to catch fire.

However, NZ Transport Agency are urging caution as delays are expected in the area.

Emergency services were called to the crash, just north of Snodgrass Road, about 5.20pm with a reporter at the scene describing what was a "burning mess".

"Power lines are down around the caravan and it's on fire," says the reporter.

It is understood the vehicle and caravan have gone off the road into a ditch, bringing down power lines at the same time.

No one is believed to be trapped inside the vehicle.

The reporter says the power lines are down across SH2 with the road blocked in both directions to traffic. Power is understood to be out in Te Puna as a result.