A chemical incident involving a truck in Western Australia's East Pilbara is under control after authorities declared a 2km exclusion zone.
Emergency services declared a HAZMAT incident 20km north of Newman in the Shire of East Pilbara on Wednesday.
The exclusion zone was put in place after the incident on the Great Northern Highway involving the truck, which was carrying ammonium nitrate.
The hazardous chemical is used in fertiliser and explosives products.
Firefighters responded to the incident on Wednesday, while police helped with traffic management.
Emergency services told people to stay away from the area, and said people who were otherwise travelling along the Great Northern Highway between Newman and Karijini Drive in Juna Downs should heed their advice.
Those in the area were advised to remain inside, out of the smoke or fumes, with doors and windows closed and air-conditioners switched off.
Roads in the area, including the Great Northern Highway between Newman and Karijini Drive, were expected to be closed until at least late on Thursday.
However, the Department of Fire and Emergency Services about 5.30am on Thursday said the incident was controlled, contained and was made safe.
People travelling along the Great Northern Highway between Newman and Port Hedland would no longer be impacted, authorities said.
The road reopened between Newman and Karijini Drive, with a speed limit of 60km/h.
Firefighters were monitoring the situation, and drivers were still asked to avoid the area or to otherwise reduce their speed and be aware of emergency services personnel.
