Inmates at a privately run prison east of Perth are rioting, scaling a roof of one section of the medium-security jail and setting fires in cells.
Western Australia's Justice Department says Corrective Services' Special Operations Group officers have been sent to quell the unrest at the jail in Wooroloo, on Perth's outer fringes.
"There are a number of prisoners on the roof of one block in the facility and prisoners inside the same block are causing damage, including setting fire to items in their cells," the department said in a statement on Sunday.
It said police and fire services were on site and no staff injuries had been reported.
"A command centre has been set up at the prison to coordinate the response.There is no threat to the broader community."