Accused mosque gunman Brenton Tarrant has dismissed his lawyer and plans to represent himself in court - raising concerns he could attempt to turn a trial into a platform for his beliefs.

The duty lawyer who represented Tarrant in court on Saturday confirmed to the Herald today that he was no longer acting for him.

Richard Peters said Tarrant appeared to be lucid and was not mentally unstable – other than the extreme views that he held.

Peters said that his job representing Tarrant ceased on Saturday - and that the accused gunman had told him he wanted to represent himself in future.

This raises the prospect of Tarrant conducting his own defence at trial and using the high-profile prosecution to promote his beliefs, which were detailed in a manifesto before Friday's shootings.

"What did seem apparent to me is he seemed quite clear and lucid, whereas this may seem like very irrational behavior," Peters said.

"He didn't appear to me to be facing any challenges or mental impairment, other than holding fairly extreme views."

Tarrant is facing one charge of murder, but is likely to face more. He was remanded in custody to appear in the High Court on April 5, and did not apply for bail or name suppression.

Brenton Tarrant is lead into the dock for his appearance in the Christchurch District Court. Photo / Mark Mitchell

Peters said that Tarrant had not displayed any condolences or regret, but "our discussion didn't touch on that".

He said Tarrant may want to use the trial to amplify his views, and it would be up to the trial judge to deal with that.

"I suspect that he won't shy away from publicity, and that will probably be the way he runs the trial. The job of the trial judge will be to deal with that.

"But it's not a place for any views to be put forward. It's simply there to determine innocence or guilt. The court is not going to be very sympathetic to him if he wants to use the trial to express his own views."

Peters said he did not have any issues representing Tarrant, as it was just part of his job.

"It's not an everyday event … It's difficult in this case to take a dispassionate view, but you've got to put that to one side and say, 'Right, let's simply process things'.

"My job was simply to appear in court and advise him of his rights and procedure."

He said the court could provide an amicus curiae at the trial, a lawyer who could advise Tarrant on the court's rules and how conduct his defence properly.

"For this sort of case, you'd have to have a lawyer of some experience, so I would have thought a layperson is not going to quite cut the mustard.

"In the absence of a lawyer, I think the court will appoint someone to make sure the case proceeds properly. That lawyer won't tell him what questions to ask or how to conduct the case, but say, 'These are the boundaries for arguing the case'."

He said Tarrant didn't tell him why he wanted to represent himself.

"I presume the basis for that is that he thinks the job would be done better himself. That's my guess."

Accused gunman's car removed from arrest scene

The bullet-ridden Subaru station wagon Brenton Tarrant was arrested in has been removed from Brougham St today.

Several bullet holes can be seen in the windscreen. After fleeing the Deans Avenue mosque Tarrant fired a shotgun several times at a vehicle in his way.

Accused mosque gunman Brenton Tarrant's car, with bullet holes in the windscreen, is removed from the scene of his Brougham St address. Photo / Claire Chambers

He also fired out the passenger window.

The police officers who dragged Tarrant from his car during the arrest had come straight from a training session on how to deal with armed offenders.

The Herald has obtained exclusive details about how the officers, after hearing there was an active shooter on the loose in the city, took to the streets to find him - and stop him.

The officers, who the Herald has agreed not to name, are both based in smaller towns out of Christchurch.

Their boss rural response manager Senior Sergeant Pete Stills said the pair had travelled into Christchurch to attend a training session at Princess Margaret Hospital in Cashmere.

The training was held on a disused floor of the hospital and was around room clearance and dealing with offenders in armed incidents.

Still from video showing the moment police arrest a man after ramming his car off the road. Photo / Supplied

"They were actually training when the call came through that there was an active armed offender in Christchurch," Stills told the Herald.

"They had their work vehicles there with them with firearms in them.

"They operationalised themselves and got into one car, they decided to skirt the city, they thought that's what the offender would do - rather than drive through the CBD.

"They were driving on Brougham Street because they thought if he'd just been to Linwood [the second mosque attacked] that's a route he might take."

Moments later they spotted a suspicious car.

"They saw someone fitting the description of the offender coming towards them," Stills said.

"The car was weaving in and out of lanes with its hazard lights on.

"They confirmed the rego, that it was the right car, and did a U-turn."

Stills said the officers have more than 40 years of policing between them and had the experience to handle the situation.

"They were trying to catch up with him, they were discussing tactics - did they want to pursue him?"

Stills said the officers weighed up a pursuit, where the gunman could have got away and "unleashed" on more innocent members of the public.