New Zealand confirmed six new Delta cases of Covid-19 in the community on Wednesday, including one fully vaccinated nurse from an Auckland hospital.

All six cases were linked to the first community case that resulted in the country’s second national top-level lockdown starting Tuesday midnight. That brings the total number of community cases to seven. Under the lockdown, businesses and schools are closed except for essential ones such as supermarkets and service stations, Xinhua reported.

Prime Minister Jacinda Ardern said genome sequencing results confirmed that it is the Delta variant that is linked to genome sequencing of cases in Australia’s New South Wales outbreak.

“Our case has originated in Australia,” Ardern told a press conference. The trans-Tasman free quarantine travel started in April and was suspended last month due to the outbreak in Australia’s several states.

One of the six new cases is a 20-year-old workmate of the first case announced on Tuesday who was a 58-year-old man in Auckland’s North Shore. The other three are flatmates of this workmate, with the remaining two being friends with the four cases, said Director General of Health Ashley Bloomfield.

One of the three flatmates is the fully vaccinated 21-year-old nurse who works at the Auckland City Hospital and had been working in recent days, Bloomfield said, adding that the hospital has taken some immediate actions to shut down any potential spread, including stopping unnecessary movements between wards and testing all staff and patients on the ward.

Ardern said the nationwide lockdown was appropriate.

“Our whole ambition here is: do it once, do it right. Short and sharp is better than light and long and I think we all agree,” she told New Zealand local media during a morning interview.

On mask use, Ardern said from Wednesday it will be mandatory for people aged 12-plus to wear a mask when visiting essential services such as supermarkets, pharmacies, and service stations, and staff must also wear masks. Masks must also now be worn at bus terminals and in taxis, she said.

“We know of instances where people have picked up Delta simply by walking past someone with it,” said a Ministry of Health statement.

New Zealand has moved to the top-level 4 national lockdown from midnight Tuesday after the first identified Delta Covid-19 case in the Auckland community. The Alert Level will be reviewed after three days for all areas except Auckland and the Coromandel Peninsula which is likely to remain at Level 4 for an initial period of seven days.

Fearing a prolonged lockdown in the epicenter of the Delta community transmission, fleeing Aucklanders brought their boats and caravans, and with their bikes on top of their racks, tried to get out of the city before the lockdown took effect.

As a result, residents at the Coromandel Peninsula set up their own roadblocks to curb the fleeing Aucklanders with the help of police.