New Zealand, which is currently under a snap lockdown, has traced the source of a COVID-19 outbreak with Prime Minister Jacinda Ardern saying it should help “stamp out” the virus, reports AFP.

The health officials in Auckland, where the case was reported, were trying to determine how an Auckland man contracted the coronavirus. The case was reported in the country after six months.

After various tests, it was revealed that the man had a version of the Delta strain found in Australia, and Ardern said investigations narrowed down the origin to a person who arrived from Sydney on August 7.

She said the traveller was in quarantine and hospital since arriving in the country, which means the virus had not been in the community as long as initially feared.

“We believe we have uncovered the piece of the puzzle we were looking for,” Ardern told reporters.

She said finding the outbreak’s source also increased the “ability to circle the virus, lock it down and stamp it out”.

New Zealand reported 11 new COVID cases, taking the 21, she said.

A three-day national lockdown, first in 15 months, was ordered after the first case emerged on Tuesday. Auckland and nearby Coromandel will face the restrictions for a week.

The infected traveller arrived from Sydney on a so-called “red zone” flight, arranged to bring back New Zealanders.

The person tested positive two days later and was hospitalised a week after that.

Officials said it was still unclear how the virus spread into the community and 1,000 close contacts of positive cases were being assessed.

A decision is due Friday on whether the three-day lockdown will be extended or end by Saturday.

New Zealand been successful in eliminating the virus in the community with only 26 deaths in a population of five million.