New Zealand police on Friday shot and killed a "violent extremist" who was known to the police, Prime Minister Jacinda Ardern said, after he stabbed and wounded at least six people in a supermarket in the city of Auckland. "A violent extremist undertook a terrorist attack on innocent New Zealanders," Ardern told a briefing.

Locals described a scene of hysteria in the Countdown supermarket in the capital city's New Lynn suburb.

While the authorities had earlier described this incident as a random attack and not terror-related, Prime Minister Jacinda Ardern has termed this as a ‘terrorist attack’.

"What happened today was despicable, it was hateful, it was wrong," she said.

Ardern reported that the incident began around 2:40 pm and the officers were able to shoot and kill the stabber within "roughly 60 seconds of the attack ".

She said the man, who arrived in New Zealand in 2011, entered a shopping mall in suburban Auckland and seized a knife from a display before going on a stabbing spree.

Terrified shoppers fled for the exits and video footage shot by bystanders showed men running toward the incident before a barrage of shots rang out.

Police Commissioner Andrew Coster said they had concerns about the man's ideology and kept very close tabs on him. Coster said they followed him from his home to the supermarket on Friday.

Videos posted online earlier showed panicked shoppers running out of the mall and looking for cover.

Auckland is in a strict lockdown as it battles an outbreak of the coronavirus. Most businesses are shut and people are generally allowed to leave their homes only to buy groceries, for medical needs, or to exercise.