The Australian man accused of killing 51 worshippers in an attack on two Christchurch mosques last year has changed his plea to guilty.

Brenton Tarrant, who was due to stand trial in June on 51 charges of murder, 40 charges of attempted murder, and one count of terrorism, admitted carrying out the attacks in a High Court hearing in Christchurch on Thursday morning.

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TVNZ, one of just a handful of media outlets allowed into Thursday’s hearing due to New Zealand’s COVID-19 lockdown, reported every name of Tarrant’s victims was read to him before he entered his guilty plea.

Justice Mander imposed a one-hour embargo on reporting the news to allow for survivors and the families of victims to be informed, before the wider public.

“It is regrettable that the Covid-19 restrictions that presently apply do not permit victims and their families to travel to be present in the courtroom when the defendant entered his pleas of guilty,” he said.

A sentencing date is yet to be set, but Mr Tarrant can be expected to face life imprisonment.

Tarrant, who describes himself as a far-right fascist, came to his radical views from conversations in dark corners on the internet, consolidated on trips to Europe.

He moved to New Zealand in 2017, settling in the South Island town of Dunedin.

Tarrant carried out his attacks on March 15 last year, carrying camera equipment that allowed him to live-stream his horrific crimes.

He was apprehended by police after fleeing the Linwood Islamic Centre, the second of two mosques targeted, after the Al Noor mosque.

Tarrant also published a manifesto detailing his hateful views. Both the live-stream and the manifesto are illegal to obtain or read in New Zealand.

The immediate reaction to the pleas was relief.

Tony Green, of the Al Noor mosque, said the sudden decision caught his community by surprise.

“There has been a mighty flurry of WhatsApp messages and the overriding quality through all of those is of enormous relief,” he told AAP.

“Many tears. And that speaks to the kind of anguish that continues to run through the community.”

Mr Green said the long-running judicial process added to the trauma suffered in the March 2019 mosque attacks.

“The protracted nature, being held in suspension by the court process, that has exacerbated the grief,” he said.

“There will be now a welling of emotions, driven by relief as people try once again to make sense of a new state.”

Aliya Danzeisen, of the Islamic Women’s Council, said it was “a blessing families don’t have to go through trial” on Twitter.

Omar Nabi, who lost his father Haji Daoud Nabi as he prayed at Al Noor Mosque, welcomed the change of heart.

“It’s about time. His plea should have been earlier but it’s good he’s changed his mind. And good to have it done,” he told the NZ Herald.

“There shouldn’t have been a trial anyway … he was caught red-handed, it speaks for itself.

“God will give him his own punishment. Just like on earth, you are punished, and when you die your soul will be tried.”

Energy Minister Megan Woods, the government’s most senior MP from Christchurch, said “I know the huge relief so many people in Christchurch will be feeling now that they do not have to face the trial and reliving the horrors of that day”.

Christchurch mourned the first anniversary of the event earlier this month, though a national remembrance service was cancelled due to coronavirus restrictions.

Tarrant has been remanded in custody until May 1.

–with AAP