Perth has become the third state or territory capital to be plunged into lockdown in less than 72 hours following the emergence of the highly-infectious Covid-19 Delta variant.
Western Australia Premier Mark McGowan once again put his state's capital under stringent restrictions for a minimum of four days following the emergence of a second locally acquired case on Monday.
"We're hopeful a four-day lockdown and all of the measures we're putting in place will be enough to crush and kill the virus in its tracks," he told reporters on Monday evening.
The lockdown began at midnight Monday and will be enforced in Perth and Peel.
Residents will only be allowed to leave their homes for essential work, essential shopping, medical reasons including vaccination and caregiving and exercise.
People cannot venture more than 5km from their homes and exercise for a maximum of one hour.
Masks will also be compulsory outside the home.
The third case detected by health authorities is a man in his 30s. He is believed to have contracted the virus at the Indian Ocean Brewery.
The man dined at the brewery last Tuesday, eating at a different table to a woman who returned from Sydney and subsequently tested positive to the Delta strain of the virus.
"What is even more concerning is this most recent infection appears to have involved only fleeting contact with the original case," Mr McGowan said.
Another woman, aged 32, also tested positive after coming into contact with the original case.
"We don't know how many more people have acquired it via this technique. That's why we're engaging in the measures which are pretty strong."
Mr McGowan said there was concern due to the man spending time in the community while infectious.
A growing list of exposure sites is available on the WA Health website.
The lockdown follows a two-week lockdown for Sydney and surrounding areas while the Northern Territory extended its lockdown to at least Friday following an outbreak linked to a gold mine.
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