Australia, which showed early signs of quashing the coronavirus, is now battling spikes in its second-most-populous state, Victoria, leading the authorities to announce lockdowns in 10 postal codes in the greater Melbourne area from 11:59 p.m. Wednesday night.

On Tuesday, the state recorded 60 new cases, its 14th consecutive day of double-digit increases. Thirteen of the cases were linked to known outbreaks, 20 were identified through routine testing and 31 more cases were under investigation, the authorities said.

The country of 25 million people reported just seven cases in its other states on Tuesday.

The numbers pale in comparison to the United States, which has seen tens of thousands of infections reported in recent days, and other countries struggling to limit the spread of the outbreak. But the new cases represent a step backward for Australia, which had begun to return to a relative sense of normalcy and had been internationally praised for its success in battling the virus. Some states have seen no new cases of the virus for weeks.

The spikes in Victoria were partly traced to large family gatherings where people failed to observe social distancing, the authorities said. Public health experts have also criticized the government for failing to communicate restrictions effectively to non-English-speaking neighborhoods in Melbourne.

On Tuesday, the state of Queensland said it would open its borders to the rest of Australia on July 10, but would exclude anyone who had been in Victoria in the previous 14 days. South Australia also scrapped plans to open its borders with Victoria on July 20.