A Fonterra site in Hamilton has been evacuated due to an ammonia leak.
Fire and Emergency told Newshub authorities were called to the Te Rapa site at about 2:45am on Friday. Five crews attended, but Area Commander Daryl Trim says this is being scaled back to two crews.
"There is still ammonia leaking at the moment, but it seems to be contained within the site," he told Newshub at 7am.
He said "one vessel" is leaking, but responders aren't yet able to go into the affected area to stop the leak.
"It starts in a liquid form and it leaks out and it evaporates off from there. That will be what's happening in the room."
It's not yet clear what caused the leak, but it could take all day to sort out.
A Fonterra spokesperson said Fire and Emergency New Zealand were managing the situation and "conducting a safe release of the gas which is a visible cloud".
Workers have been evacuated and many have headed home.
There have been no reports of injuries and Fonterra says the leak hasn't disrupted operations as the site was on "winter shutdown and under maintenance".
"If people do smell ammonia and if they think it's strong, give us a call and we will come and have a look," Trim said.
