A primary school and a kindergarten near the southern hemisphere's biggest drug lab, raided in Fiji last week, have been ordered closed because of danger from highly toxic fumes.
Health officials have told more than 700 nearby residents and workers to be ready to vacate their homes temporarily over health and safety concern.
Officials fear contamination of ground and water outlets in the area.
Already residents living close to the drug factory say they are suffering from skin and eye irritations and a choking feeling in their throats.
Workers at an adjacent timber yard are also complaining of health problems, with one being forced to take leave.
A health ministry spokesman says they have put an emergency medical team on standby.
The danger could increase today when New Zealand police specialists wearing protecting clothing and breathing gear open unlabelled drums of chemicals.