A freight train derailment in the central North Island has resulted in a gas leak.
The incident happened between Waiouru and Taihape just after 10am, Inspector Mike Coleman of central police communications said.
The gas is the refrigerator gas Argon, which is not toxic or flammable.
It was not yet known how the wagon came off the rails, he said. No injuries were reported.
A KiwiRail spokeswoman said the front wheels of one of the 39 wagons had derailed.