Fire crews are responding to an alarm at the Fonterra plant in Southland.
A Fire and Emergency New Zealand spokesperson confirmed the call out was received at 3.40pm.
It was believed a drier had overheated and sent the sprinkler system off.
Two engines were initially sent to the scene, she said.
"They've just asked for two more because they need extra breathing apparatus.''
A police spokeswoman confirmed Fire and Emergency New Zealand had notified police of the alarm at the Edendale plant on North Rd.
More to come.
