Fire and Emergency crews are currently in attendance at an ammonia leak in Dannevirke. Photo / NZME
What caused an ammonia leak at Oringi Business Park is now under investigation by Icepak New Zealand.
Crews from Dannevirke and Woodville as well as Napier and Palmerston North were called in.
Traffic control was put in place along Oringi Road and the public were advised to avoid the area if possible.
A spokesperson for Fire and Emergency New Zealand said they were called to the site about 8.30am.
He said crews in "level 4 gas suits" are getting entry to confirm if the leak has been contained and investigations were ongoing.
Logan Miller, general manager of health, safety and assurance for Icepak which manages the site, said the incident had been reported to WorkSafe who would be visiting the site.
"Emergency services are attending and all our teams and others near the site have been evacuated as a precaution."
It was believed the leak occurred during maintenance to the plant, after what appears to be a valve failure.
Miller said the response plan had worked as intended.
"While this kind of incident is disruptive the key is that everyone is safe and our people and others will remain off-site until the all-clear is given."
He praised the quick response from local fire services who had set up a wide cordon and perimeter given unpredictable wind conditions.
Lee Bettles, chief executive of Scanpower which owns the Oringi Business Park complex where the leak occurred, said the leak was isolated "very quickly".
The site, which has about eight businesses operating from it, was cleared as a precaution.
Cordons were lifted around 12.30pm and emergency crews left the scene.
Restrictions have been placed on all outdoor fires in parts of Hawke's Bay.