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.
Early voting for Secret Harbour by-election begins Monday
Welfare concerns for missing Swedish national last seen in Warnbro
Wanted man last seen in Golden Bay
Passenger critically injured in West Pinjarra crash
Unregistered painter fined for requesting hefty deposit from Singleton homeowner and not doing the job
Police hunt driver following dangerous Baldivis pursuit
Welfare concerns for boy last seen at Port Kennedy skate park
Rubbish truck catches fire in Baldivis
Driver injured in bus crash in Rockingham