He said there are no longer any homes under immediate threat from fire and there have been no reports of any homes sustaining damage.
A KiwiRail spokeswoman said it was investigating how the fire started, but believed it was “likely” due to sparks from the brakes of the train.
“A freight train shunting wagons from a milk factory in West Rolleston was held back near Darfield earlier today after it created a number of grass fires along the track,” she said.
“The train was stopped while the incident was being investigated. No one was hurt.”
The rail track is now closed overnight between Rolleston and Darfield.
Affected services overnight include the TranzAlpine travelling from Greymouth to Christchurch with 172 passengers on board. Overnight freight services are also affected.
Bus replacements are in place for the TranzAlpine passengers.
“We are sorry for the inconvenience, but safety has to be our top priority,” the spokeswoman said.
A Fenz spokesman said it received multiple calls about fires along railway tracks between Rolleston and Darfield, west of Christchurch, around 4.15pm.
Three helicopters have been fighting the fires, alongside 17 ground crews, including pumps, tankers, smoke chasers and a command unit.
Crews are in attendance from Kirwee, Darfield, West Melton, Hororata, Dunsandel, Springfield, Wigram, Canterbury High Country, as well as the Christchurch command unit.