Update, 7.40pm: A fire which has closed part of Tonkin Highway and posed a potential threat to Forrestdale homes has been brought under control.
Fire crews at the blaze bear Armadale Road and Tonkin Highway have the fire contained and under control.
The Department of Fire and Emergency Services has downgraded the fire alert for the area bounded by Armadale Road, Tonkin Highway, Ranford Road and Lake Road to an 'advice' warning.
DFES says the fire no longer poses a threat to lives and homes although there is still smoke in the area.
People in the area are being encouraged to stay vigilant and watch for signs of a bushfire.
The fire is slow moving and is heading east. Two fixed-wing waterbombers and a helitac were at the scene helping the 62 firefighters at the blaze.
The Tonkin Highway remains closed in both directions between Ranford Road and Armadale Road.
Main Roads has advised motorists to avoid the area and has warned to poor visibility due to smoke.