And it has emerged that multiple warning signs were there, from a former soldier who raised concerns about extremism at Tarrant's gun club in Dunedin to warning emails sent to the prime minister's office that were not seen until after the attack.
His 21-year-old son Talha also was killed at the Al Noor mosque.
He added that the country was proud of Naeem Rashid, one of the victims, who the premier said would be recognised for his courage with a national award.
A senior Government source said it was thought Tarrant, who was not on a "watch list", "transited" through the United Kingdom and stayed "for a few weeks".
At a Sunday news conference, Arden used some of her strongest language yet about gun control, saying that laws need to change and "they will change".
"But that arrest was tangential to this matter and we do not believe that he was involved in this attack either", he said.
He remains the only person charged directly over last Friday's shooting massacres. Afghanistan's embassy in Canberra named Nabi as one of two Afghans killed in the attack. "Just helping people is his main thing".More news: 'Game of Thrones' final episode lengths, dates revealed
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Members of New Zealand's Muslim Association in Auckland travelled to Christchurch to help with Muslim funeral rites, which consists of washing the bodies, wrapping them in white cloth and moving them to the cemetery.
She also signalled that if convicted, he would serve his sentence in New Zealand.
The Pacific has reacted with sadness and shown solidarity for New Zealand after at least 49 people were killed in shootings at two Christchurch mosques yesterday.
According to a recent report from the Anti-Defamation League (ADL), domestic extremists killed 50 people in the United States a year ago - an overwhelming majority of which were perpetrated by right-wing extremists.
In Sydney, a silver fern - the symbol of New Zealand - was projected onto the side of the world famous Opera House. Until Friday, the country's worst mass shooting was in 1990, when a lone gunman killed 13 people in the small town of Aramoana.
He said he survived by playing dead, but was desperate to know what happened to his friends who were there with him.
Moreover, Pakistan's High Commissioner and Deputy High Commissioner in New Zealand would also be available for guidance, round the clock, the press release said.
It also said a group of Community leaders is being constituted in Christchurch and their names and numbers will be circulated shortly.
Pence also affirmed US cooperation in ensuring all the perpetrators were brought to justice. "We are filled with grief over this senseless act of hate".