Perth will go into a mandatory three-day lockdown from midnight tonight (2am AEST), after a fourth case of transmission was detected from WA’s hotel quarantine system.

A Victorian man in his 50s who was infected at the Mercure hotel was in Perth for five days in the community while possibly infectious.

The man stayed with a friend who has today returned a positive test result to a rapid serology test.

During the three-day lockdown, people will only be able to leave home for work, shopping for essential items, medical and healthcare needs and exercise.

From 6pm tonight AWST (8pm AEST) masks will be mandatory and anyone who left the Perth or Peel region from April 17 will be required to wear a mask.

100 people can attend funerals and weddings, ANZAC dawn services have been cancelled, and no crowds will be permitted to attend the AFL game on Saturday night.

6PR host Simon Beaumont told Jim Wilson it’s a “devastating blow”, especially on the eve of ANZAC Day.

“This rumour started circulating in the community at 11 o’clock [Perth time] and everyone stormed the shops.”

The frustration for Perth residents, he said, is not the reaction from the government, but the fact that it’s needed in the first place.

“How does this keep getting out of our hotel situation? … That is where the backlash will come.”

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