New Zealand's PM says scientists have solved COVID outbreak "puzzle"

• The World Health Organization has praised New Zealand for its rapid COVID-19 genome sequencing and "unique" targeted modeling technology that can predict down to the suburb where the coronavirus might spread.

What they're saying: "Today we believe we have uncovered the piece of the puzzle we were looking for," Ardern said at a news conference Thursday.

• "And that means our ability to circle the virus, lock it down and stamp it out generally has greatly improved."

The big picture: Ardern imposed alert level 4 restrictions nationwide following the first positive test result in the community for nearly six months.

• As the number of coronavirus cases in the Auckland community rose to 21 on Thursday, Ardern announced that 12- to 15-year-old children would be eligible for the vaccine from Sept. 1.

Of note: Officials see lockdown enforcement as another key tool in once again banishing the virus from the community. There's a visible police presence across the country and police have made several arrests for health order breaches.

• Police prosecuted dozens of people for breaching pandemic rules during NZ's only other nationwide lockdown, early in the pandemic.

Editor's note: This article has been updated with new details throughout.