Police are hunting an arsonist who they believe ignited the Marsden Park fire which destroyed one home and put hundreds of residents on evacuation alert on Tuesday.
NSW Police Force Assistant Commissioner Alan Clarke said investigators ‘‘suspect arson activity’’ caused the huge fire which started on the fringes of Grange Avenue about 12.15pm and burnt through more than 10 hectares of bushland within hours.
Police want to speak to anyone who may have witnessed anything suspicious near the Marsden Park area around the time the fire started.
Investigations into the other three blazes which ravaged western Sydney and the Blue Mountains continue.
Early investigations reveal the Richmond Road fire was caused by powerlines falling on trees in high winds near The Driftway, which sparked flames in the area.
The cause of the Tickner Road, Londonderry, fire is still unknown.
NSW Rural Fire Service Deputy Commissioner Rob Rogers said the Winmalee fire was the result of a hazard reduction burn carried out by National Parks and Wildlife Service over the weekend.
Police said bushland in the area was still smouldering on Tuesday when flames broke through containment lines as winds picked up.