The gunman posted a 74-page manifesto on social media in which he identified himself as Tarrant and said he was a 28-year-old Australian and white supremacist who was out to avenge attacks in Europe perpetrated by "Muslims".
He did not request bail and was taken into custody until his next court appearance which is scheduled for April 5.
"There is one charge of murder brought at the moment, it is reasonable to assume that there will be others", said Judge Paul Kellar. While he allowed media persons to take photographs and film the proceedings, he ordered that Tarrant's face be pixelated as his identity might be a part of the court case. It was later notified that one of the detained was later let go.
"I think we must be clear that the context of the gun laws between New Zealand and Australia are very different", Australian Prime Minister Scott Morrison said on Saturday.
Earlier today Ardern led a cross-party group of politicians, including Deputy Prime Minister and NZ First leader Winston Peters, Opposition leader Simon Bridges, Green Party co-leader James Shaw and senior ministers on a visit to the Canterbury refugee centre.
The manifesto also said he chose to make his attack in New Zealand to show that nowhere in the world was safe.
Tarrant's relatives in the Australian town of Grafton, in New South Wales, contacted police after learning of the shooting and were helping with the investigation, local authorities said.
A short distance away, 39 people were being treated in hospital for gunshot wounds and other injuries inflicted in the massacre.
Two men were filmed brandishing what appears to be hammers during a street altercation in London before one jumps on the bonnet of a vehicle, with broken windows, as it drives off.
He said Muslims at a Levenshulme mosque "beamed" when they saw his act.
Trump said: "I don't really".
After her press conference, New Zealand Attorney General David Parker promised a crowd at a vigil for the victims of the shooting that the government would ban semi-automatic weapons, according to the New Zealand Herald. Anyone can use a pistol if they are on the range of an incorporated pistol club that is recognised [sic] by the Commissioner of Police, and under the immediate supervision of a licence [sic] holder with a B endorsement.
Ansun Zhong, owner of Chong's Chinese restaurant in Christchurch City Central, said the shooting greatly affected people's life in Christchurch.
Following the attack, mosques around the country remain closed until further notice.
New Zealand Police Commissioner Mike Bush said additional charges are forthcoming.
None of those arrested had a criminal history or was on any watchlist in New Zealand or Australia.
Prime Minister Jacinda Ardern vows to change gun laws as soon as possible in the wake of the Christchurch terror attack.
Ardern said Saturday that she had met with relatives of the victims and their "key concern" was to have access to their loved ones' remains for burial.
Desperate for any news, families and friends of the victims gathered at the city's Hagley College, near the hospital.