Anyone venturing out in Australia's second-biggest city was ordered Thursday to wear a mask as authorities struggle to contain multiple coronavirus clusters in the country's southeast.

Most people seen by AFP on the quiet streets of Melbourne's city centre wore masks in the second week of a six-week local lockdown. Victoria state, of which Melbourne is the capital, recorded 422 coronavirus cases on Thursday -- a dip from a record peak of 484 on Wednesday, but its 18th consecutive day of triple-digit rises.

The mandatory mask order allows police to issue fines of Aus$200 ($140) to anyone who refuses to cover their face in public, although previous lockdown rules have generally been enforced with warnings.

The state's leader said the lockdown restrictions had helped stabilise infection numbers, but the next step was driving them down. "Stability is not enough; stability won't get us beyond this," Premier Daniel Andrews told media. "We have to also see compliance in the community at extraordinarily high levels."

Locals seemed to have delivered, with those commuting through Melbourne telling AFP they were still adjusting to the mandatory face coverings, which are freely available in city shops. "It's really unusual to see... it's just not normal," Zoie Dicker said.

Elsewhere in Australia, masks are rare. But the rising number of cases in Victoria has heightened calls for tighter restrictions as the outbreak dampens hopes of a speedy recovery from the epidemic. "We should go to... whatever is necessary to just eliminate the thing and go back to what's left of our normal lives," Melbourne resident Adam Ozmen said.

Victoria has effectively been sealed off from the rest of the country in an effort to contain the virus, but new cases have been detected in neighbouring New South Wales state -- sparking tighter restrictions in its capital, Sydney. Australia has now recorded more than 13,300 cases of the virus and 133 fatalities among its population of about 25 million.

Melbourne was not the only city to bring in a mask law this week, with a similar initiative in the US capital. The mayor of Washington ordered city residents to don face coverings as soon as they leave their home. "People must wear a mask when they leave their homes if they are likely to come into contact with another person for more than a fleeting moment," Muriel Bowser's office announced.