Fire and Emergency New Zealand was alerted to a large fire involving hay bales in Winslow, Ashburton around 11.30pm last night.

Incident Controller Carrie Swanson says that at its peak, the fire was fought by 11 fire crews and additional support staff.

"Thanks to the hard mahi of our crews, no other structures were damaged besides the two hay sheds," she says.

"The fire was contained to this property, and no others are currently threatened.

"The fire began to decrease in size around midday today, but it is large and deep-seated, and will take some time to cool and extinguish completely."

Crews will continue to work on the fire overnight and into the next few days, Carrie Swanson says.

"Don’t be alarmed if you see smoke in the area, as this is to be expected," she says.

"If you’re in the vicinity and are concerned, stay inside and keep doors and windows closed."

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