Two firefighters have been hurt battling a major fire at a farm feed factory in Ashburton.
The crew members were taken to Ashburton Hospital as a precaution after suffering minor burns to their legs, Southern Fire and Emergency NZ southern shift manager Brent Dunn said.
The spectacular fire is at SealesWinslow, a feed manufacturer that produces pelletised feed and blocks of molasses for cattle and sheep farmers.
There are now 21 fire appliances at the scene and more than 50 firefighters, Dunn said.
The operation will continue through the night, he said. A heavy digger is being sourced to help with the salvage.
"We've got appliances from Christchurch heading down now for relief crews. We are going to be there for some time but they're mostly volunteers and we're aware that they've got jobs to go to tomorrow."
Thick black smoke could earlier be seen pouring into the air from the fire at the factory on State Highway 1 in Winslow, halfway between Ashburton and Hinds.
The fire service was called at 7.40pm. The feed-processing shed measures 100m x 50m x 20m and about half the shed was well ablaze, Dunn said earlier this evening.
Apart from the two firefighters no one was reported injured in the fire.
Dunn said it was not known how the fire had started and fire investigators would be looking into the cause on Tuesday.
Ashburton had its driest November since records began in 1909 and has experienced temperatures well above average, with residents facing water restrictions.
The temperature in Ashburton hit 27C today and is now hovering around 18C.