There were seven people injured in yesterday's attack at the New Lynn supermarket, with three still in a critical condition.

While there were six injuries initially reported, the Prime Minister this afternoon updated the number of injured in the attack to seven, saying five are in hospital, with three in a critical condition.

Police commissioner Andrew Coster says there was nothing unusual with the assailant's behaviour. He travelled to the supermarket by train. He was shopping normally with a trolley for about ten minutes before the attack.

Surveillance teams work hard not to be recognised, otherwise the surveillance becomes uneffective, says Coster. This is why police teams were not in the supermarket with him, instead staying near the entrance to the supermarket.

"Monitoring the terrorist's actions has been reliant on teams being able to maintain their cover."

Coster acknowledges those who stepped in to help, including members of the public. He also acknowledges the victims and their families.

"They will be going through great anguish as a result of this horrific situation."

Event like this can bring out "disturbing attitudes" from those in the community, Coster says. Police would maintain a high presence around shopping centres and gathering spots to monitor this.

Coster says there was a lot of misinformation circulating about the attack, and encouraged people to be careful with what they chose to believe.

"This case is an outlier, and we are not looking for anyone else."

Ardern says while she was working for the man's name to be released, she was not intending on naming him herself.

"No terrorist, whether alive or deceased, deserves their name to be shared for the infamy they were seeking."

Since 2016, the man has been charged multiple times for possessing hunting knives and restricted, objectionable publications.

In July, the individual was released back into the community, marking the start of his surveillance, Ardern says.

In late July, the PM was given an update on the case, and in August, met with officials to discuss further options in reducing the risk the man posed to the community.

Later in August, the police commissioner raised the possibly of expediting the amendments to the counter terrorism legislation. Within 48 hours, the Minister of Justice contacted the chair of the select committee with the intent of speeding the law change up.

"That was yesterday, the same day the attack happened."

Ardern says agencies used every tool available to them to protect innocent people from the man.

"Every legal avenue was tried," says Ardern.

"We must be willing to make the changes that we know may not have changed history but could change the future.

Changes to terrorist suppression rules are underway. The public have had their say on this already, says Ardern.

When Parliament resumes, Ardern says they would work to have the law changes as soon as possible - hopefully by the end of the month.

Ardern acknowledges the work of police in monitoring the man, and those who responded at the scene.

"To the Auckland community, times are tough, and I know that you will be feeling it right now, but we are all with you."

She ended with words from the Iman at the Masjid Al Noor Mosque in Christchurch.

"All terrorists are the same, regardless of their ideology. They stand for hate, we stand for peace and love."

Ardern says it wasn't fair to make an assumption that the law change would have made a difference here.

"We don't know that to be true,” says Ardern.

"This was a highly motivated individual who used a supermarket visit as a shield for an attack. That is an incredibly tough set of circumstances."

The first point at which the Government was alerted of concerning material posted on Facebook was in 2016, five years after the Sri Lankan national arrived in New Zealand.

Coster said it was unclear if the man had planned the attack or was opportunistic.

"We will probably never know the answer to that. We do now he was surveillance conscious."

CCTV showed the man had removed a kitchen knife from a shelf in the supermarket. A knife fitting that description was found next to the man's body, Coster says.

"Nothing suggests to me anything other than the knife was obtained in the store."

All seven victims were injured as a result of the offender's actions, rather than due to police actions, Coster says.

The man had been uncooperative with attempts to modify his behaviour or address his underlying psychological issues, Coster says.

Police had been surveilling the man for 53 days prior to the attack.

Meanwhile, New Zealand's two major supermarket companies have removed knives for sale at their stores after yesterday's terror attack at the Countdown in New Lynn.

In a statement released this afternoon, Countdown spokesperson Kiri Hannifin says the company had made the decision to temporarily remove all knives and scissors from its shelves "while we consider whether we should continue to sell them".

"This is in no way a reflection on our customers, but an act of support for our team. We want all of our team to feel safe when they come to work, especially considering the events of yesterday."

Foodstuffs, which owns the Pak 'n Save, New World and Four Square brands, says it was also removing sharp knives from sale "while we consider the event and take some time to review the safety of our customers and staff".

Ardern said it wasn't fair to make an assumption that the law change would have made a difference here.

"We don't know that to be true."

"This was a highly motivated individual who used a supermarket visit as a shield for an attack. That is an incredibly tough set of circumstances."

Stuff