Police Association President Chris Cahill has praised the "world-class" work by New Zealand Police after new figures show they were at the scene of the Christchurch terror attack in less than six minutes. 

Revised figures reveal it took 5 minutes and 39 seconds for police to be armed and on the scene ready to respond to the attack. In 10 minutes the armed offenders squad was on the scene.

Chris Cahill told Mike Hosking the alleged gunman was arrested within 21 minutes.

"It's been a really tough few days. But as everything has unfolded it has just filled me with pride as to the magnificent response of officers, right from the initial ones through to people who are turning up throughout the country now and working 12 to 13-hour shifts to keep Christchurch safe."

"A very proud time."

Following the attack, it was revealed that the officers who arrested the alleged gunman, had come straight from a training session. 

However, Cahill said training is very different from the real event. 

"You can think you might act, and they will say every cop would have done the same, but that's not necessarily true. To make the split-second decision that we have to take this person out or other people are going to be in danger and then act...incredibly well done."

When asked about criticism that the arrest took too long, he said it was mostly coming from international media. 

"I tried to find that [criticism] and to be honest, a lot of it was driven by overseas media who were trying to find a story."

"The people of Christchurch haven't said that at all. I've been around cordons and they have been coming up and hugging officers," he said.

"I think what we have seen now that the facts have come out, that it is actually world class."

The Police Association President also said semi-automatic weapons need to be banned. 

"The first thing they should say is that military-style semi-automatics and there high powered equivalent rifles are gone tomorrow."

"We do need a gun register in  New Zealand and maybe that's the second stage in the next couple of weeks."

Yesterday, Police Minister Stuart Nash praised the quick work of the police, saying the officers are heroes.

Speaking with Mike Hosking, Nash said the alleged gunman was shooting his gun and yelling "I've got a bomb" during his arrest.

The police officers who arrested the 28-year-old have been hailed as heroes and the Police Minister agrees. 

He said the officers remained calm and collected during the ordeal and are "heroes".

"These two guys pull this guy out but at the same time he was yelling, 'I've got a bomb' and shooting at the same time, so we overuse the word hero but not in this case."

"I'm very, very proud to be their Minister. I just think they have stood up when they needed to. I'm very proud of them."

He also addressed criticism around the time it took for the police to arrest the alleged gunman. 

"The Commissioner and his team are looking through all the transcripts and the voice recordings and we think it might be as low as 20 minutes, the Commissioner can't believe it's that short," he said.

"We are talking about a big city, a widely spread city, to have the guy arrested either within 20 minutes or 35 minutes, I think is extraordinary."

When asked whether the officers would be receiving bravery awards, Nash said he can't "preempt anything" but there "aren't too many more acts of bravery higher than that".

Stuart Nash said while they may have been training for it, nobody expected the day to end as it did.

"They do train for this but they just showed an extraordinary level of calmness."

"When these guys were confronted with a chap...who was firing shots, who said he had a bomb, they were calm and they executed their duties in a way that I think was extraordinary. [I'm] full of praise."

National MP Mark Mitchell agrees, saying the police officers showed a huge amount of bravery and professionalism.

He also applauded the work of the first responders and hospital staff who dealt with the "horrific scene".

"We can be so proud of them. We need to find a way to recognise all of them."

"There are going to be more and more unsung heroes, who emerge and come out of what has been a terrible tragedy for us as a country, but shows the fibre and the metal of what we are made of."