Christchurch mosque shootings: 'A turning point in our politics' says Paul Buchanan, as focus goes on right-wing extremism

New Zealand has been "infected with the virus of homicidal politics" by extremism that hasn't been a big enough focus for intelligence agencies, a security analyst says.

Paul Buchanan, director of 36th Parallel Assessments, said today's attacks in Christchurch were "a turning point in our politics, and for society in general".

"We have now been infected by the virus of confrontational, to the point of homicidal, politics that is seen all too often in the United States and Europe. And it has now come home," he told the Herald.

"This is big trouble. This is a watershed moment for us."

Since the 9/11 terror attacks in the United States, the focus of New Zealand's intelligence and security services had been on the threat from Islamic extremism, Buchanan said, and limited resources meant there hadn't been enough attention given to the threat from right-wing extremists.

"Right-wing extremists have been very visible, very vocal in Christchurch and have carried out attacks on minority communities regularly over the past decade or so. This is not surprising, as terrible as it is, because of that."

A manifesto written by one of the gunmen was "straight out of the white supremacist playbook", Buchanan said. Obvious social media activity dated back until at least February.

Intelligence agents would be working to find the person's associates, and to work out if they were part of a wider cell. Other questions would be where the weapons came from, and how the shooters learnt to operate and possibly modify them.

"It's tough as an intel guy, because all your successes are never revealed, and when you make a mistake ... but they obviously now have to spend renewed attention on right-wing extremists," Buchanan said.