Out of control, unpredictable fire stalks homes in Pilbara

A watch and act bushfire alert has been issued for people in Tom Price and the western part of Karijini National Park in WA's Pilbara region. 

"There is a possible threat to lives and homes as a fire is approaching the area and conditions are changing," the Department of Fire and Emergency Services said in a statement issued this afternoon.

"You need to leave or get ready to actively defend."

The bushfire is moving slowly west.

Twenty volunteer Fire and Rescue Service, Bush Fire Service and Department of Parks and Wildlife firefighters are at the scene.

The cause of the fire is unknown.