Emergency services have given the all-clear after a four-hour chemical alert at Affco's Wairoa plant today.
Fire and Emergency New Zealand's Wairoa Volunteer Fire Brigade was called at 6.56am and along with the Wairoa District Council warned mid-morning there had been an ammonia leak.
The risk was considered low but residents were warned as a precaution to stay inside, close all windows and doors and wait for further instructions.
National highways management agency Waka Kotahi NZTA reported the closure of the Hunter Brown St to Mahia Ave sector of State Highway 2 through the town, part of the main road from Wairoa to Gisborne, but there were alternatives.
It was reopened with some restrictions by 9.20am, and the Council announced just after 11am the all-clear had been given and residents and businesses could return to normal activity.