Eight crews — four from Oamaru, and one from Glenavy, Hampden and Weston — were called to the fire in Old Mill Rd about 4.49pm, a Fenz spokesman said.
The crews were able to keep the blaze under control, and were finishing mopping up about 6.20pm. No property was damaged in the fire, and there was nothing to indicate the fire was suspicious, the spokesman said.