An Islamic extremist and self-proclaimed ISIS supporter was shot and killed by police in New Zealand Friday. The man reportedly attacked at least six people inside a local supermarket. Authorities said the "terrorist attack" occurred in the Auckland suburb of New Lynn.

Prime Minister Jacinda Ardern confirmed the incident in a news conference Friday afternoon. She said police were able to take down the man before he could hurt anyone else.

"This afternoon at approximately 2:40 p.m., a violent extremist undertook a terrorist attack. This was a violent attack, it was senseless, and I am so sorry it happened," Ardern said.

Authorities identified the man as a Sri Lankan national who was a "known security threat." The man was reportedly already under constant surveillance by multiple government agencies.

Ardern said police were able to shoot and kill the man within 60 seconds from the start of the attack. The man was reportedly a strong supporter of ISIS ideologies.

New Zealand Police Commissioner Andrew Coster said the man had entered the supermarket and obtained a knife within the store. He reportedly stabbed and slashed at least six people, three of whom are now in critical condition.

Video of the attack was also posted online, showing panicked shoppers running out of the LynnMall Shopping Center. After the man was taken down by police, ambulances immediately arrived to care for the injured. Police then cordoned off the surrounding streets not long after.

Authorities said the man had arrived in New Zealand in 2011. He was then marked as a person of interest in 2016. The man's identity was not made public but officials said he had faced court in the past.

Ardern said there was a suppression order in place, which is why they aren't allowed to release certain information about the attacker. Ardern added that she was "personally aware" of the man and the threat he posed before the attack.

The attack occurred while Auckland was still under Level 4 lockdown, which meant that most establishments were closed except for essentials such as supermarkets.

Countdown, the company that operated the supermarket, said it was "devastated" to learn about the attack. The company expressed its sympathies for the customers and staff affected by the attack.