New Zealand had beaten COVID-19, but now its biggest city is back in lockdown

New Zealand, which has been praised for its handling of the coronavirus pandemic, placed its largest city back into lockdown Wednesday after the country recorded its first COVID-19 cases in more than three months.

Four members of one family in Auckland tested positive, causing Prime Minister Jacinda Ardern to reimpose tight restrictions in the city and social distancing measures across the entire country until at least Friday.

To complicate the situation, health officials said two members of the infected family had visited tourist sites in the town of Rotorua, about 140 miles southwest of Auckland, expanding the number of people who could have been potentially exposed. The family had not traveled overseas.

“As we have seen in other countries where a resurgence occurs, it’s incredibly important to act early,” Director General of Health Ashley Bloomfield said.

“We have done this before and we can do it again," he added.

Residents of Auckland, a city of around 1.7 million people, were given very little time to prepare for the return to level 3 restrictions, requiring people to stay at home, work from home and, if possible, wear masks when going outside. All schools, public facilities, bars, restaurants and businesses were also shut.

Police set up roadblocks to discourage a mass exodus from Auckland, while supermarkets rationed the sale of some staple products amid a rush to the shelves. Long queues formed at COVID-19 testing centers in the city.

Although the source of the virus is unknown, health officials are probing whether the virus may have been imported by freight.

New Zealand, which holds a national election mid-September, has managed to keep the virus in check throughout the pandemic, recording 1,225 confirmed cases and 22 deaths.

Although it has a small population, with less than 5 million people, New Zealand has recorded just 4.56 deaths per million people, compared to compared to almost 500 per million in the United States, according to figures from the University of Oxford.

In June, Ardern famously said she “did a little dance” to celebrate the news that New Zealand had no active cases of COVID-19.

While the re-emergence of the virus after 102 days of no local transmission is a setback for the nation's efforts to stem the pandemic, Ardern remained optimistic.

“If we get our immediate response right in this critical phase, we have the opportunity to lessen the time that we will have those heavier restrictions, and that’s a lesson that we have all learned together,” Arden said, adding that the new restrictions will be hugely frustrating for many people.

Meanwhile, neighboring Australia recorded its deadliest day of the coronavirus pandemic on Wednesday and the biggest daily rise in infections in three days.

A cluster of infections in Melbourne, Australia’s second-largest city, caused authorities last week to impose a night curfew, tighten restrictions on people’s daily movements and order large parts of the state economy to close.

Officials in the country’s remote Northern Territory said Tuesday they will continue enforcing strict border controls until for at least until 2022.

"If you can, cancel your Christmas holiday plans and stay here in the Northern Territory,” the territory's Chief Minister Michael Gunner told Australia’s ABC News channel.

Worldwide, the number of COVID-19 cases has now topped 20 million, with the U.S., Brazil and India accounting for more than half of them, according to data compiled by Johns Hopkins University. The global death toll is hovering at over 740,000.

The virus has wreaked havoc on the global economy, with monetary effects of the pandemic leaving hundreds of thousands of people around the world out of work or relying on government furlough schemes.

The largest contraction reported by any major economy so far was announced in the U.K. on Wednesday.

Officials there said Britain’s economy shrank by a record 20.4 percent between April and June as it entered a recession for the first time in 11 years.

“Today’s numbers show that hard times are here,” Chancellor Rishi Sunak told U.K. broadcaster Sky News, which like NBC News is owned by Comcast. “Hundreds of thousands of people have already lost their jobs and many more will.”

Britain suffered the worst coronavirus outbreak in Europe with more than 46,000 deaths so far.

Reuters contributed to this report.