Firefighters pour water on an overheating KiwiRail locomotive near Henley yesterday afternoon.
A KiwiRail spokesman said the freight train was carrying empty fuel wagons and was halted after the driver noticed smoke coming from underneath one of the two locomotives.
As a safety precaution, the Fire Service was called to the scene and the locomotive doused with water to cool it down, he said.
No fuel leaked, there was no damage to the surrounding area and the service was given clearance to travel towards Dunedin.
It appeared the braking system may have overheated.
The locomotive would be inspected upon its arrival in Dunedin and all necessary repairs carried out, the spokesman said.