Six crew members from a live export ship off Perth have tested positive for coronavirus, taking the state's total case numbers to 570.
Premier Mark McGowan fears the infection numbers from the vessel could rise further, labelling the situation as "extremely concerning".
"For the time being, the remaining 42 crew members, who I am advised are currently well, will remain onboard the ship and will be monitored and undergo health assessments as required," he told reporters.
"But I suspect it is probably more than likely that more crew members may become infected with the virus. This is an extremely concerning situation that we find ourselves in."