A number of roads have been closed off to the public following an ammonia leak in Kwinana.
UPDATE: Four people have been taken by St John Ambulance to hospital after being exposed to ammonia.
Two people have been taken to Fiona Stanley Hospital and the other two taken to Rockingham Hospital but have received non-life threatening injuries.
An alert has been issued by the Department of Fire and Emergency Services following an ammonia leak in Kwinana on Saturday morning.
Kwinana Beach Road has been closed between Patterson Road and CBH Grain Terminal.
Authorities said an ammonia leak on Port Road Jetty in Kwinana prompted the closures.
People in the area are advised to remain inside, out of the smoke fumes with air conditioner units switched off.
Motorists are also asked to avoid the area with emergency crews on site.
The Department of Environment and Regulation Pollution Response Unit are providing technical support to DFES.
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