Tarrant did not request bail and was remanded in custody till his next court appearance on April 5. An eighth victim died at the hospital. They included a two-year-old boy and a four-year-old girl, who is in critical condition.
Tarrant was arrested in a auto, which police said was carrying improvised explosive devices, 36 minutes after they were first called.
A second survivor, Faisal Sayed, said: "If that hadn't happened, many more would have died and I wouldn't be here now".
A pair of rural New Zealand police officers dramatically arrested the suspected Christchurch gunman 36 minutes after authorities were alerted, it emerged Saturday, as the prime minister hailed their bravery.
"It is with great sadness that we learned today that New Zealand Futsal goalkeeper Atta Elayyan has died during the painful Christchurch attacks", Federation Internationale de Football Association said on Twitter.
"It's outrageous, the feeling is outrageous", he said.
The victims of Friday's shooting included immigrants from Jordan, Saudi Arabia, Turkey, Indonesia, and Malaysia.
Why was the country, thought of as among the most peaceful in the world, singled out for a horrifying terrorist attack?
At around 1.40pm yesterday Australian Brenton Tarrant allegedly stormed Masjid Al Noor and Linwood Masjid, and opened fire. "Our hearts are breaking for your loss", read one of the notes marked with a string of x-kisses.
"One of the issues we are facing is that the guns that were used in this case appear to have been modified", Ardern said.
In the aftermath, the country's threat level was raised from low to high, police warned Muslims against going to a mosque anywhere in New Zealand, and the national airline cancelled several flights in and out of Christchurch, a city of almost 400,000.More news: Raonic Beats Kecmanovic To Reach Indian Wells Semi-final
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She said, "The mere fact... that this individual had acquired a gun licence and acquired weapons of that range, then obviously I think people will be seeking change, and I'm committing to that".
"Your father saved my life", according to Australian newspaper The Age. The two others are in custody, while a fourth person who was taken into custody was later determined to be an armed bystander.
One man who said he was at the Al Noor mosque told media the gunman burst into the mosque as worshippers were kneeling for prayers.
"It makes me feel like he wanted other people to live".
The Queen of England released a statement, as did President Donald Trump along with many other world leaders.
"My warmest sympathy and best wishes goes out to the people of New Zealand after the disgusting massacre in the Mosques", Trump wrote.
Prime Minister Jacinda Ardern, after meeting families of Christchurch terror attacks' victims, says the country stands united and grief and that their gun laws will change in the aftermath of the attack on Christchurch mosques.
It was "reasonable to assume" Tarrant would face further murder charges, Judge Kellar said.
The attack has prompted searching questions about whether right-wing extremism has been treated with enough seriousness by Western governments.
"We never imagined this ever happening here", he said.
Earlier in the day, Mayor John Tory said he was deeply saddened by the terror attack, adding he "stands with our Muslim community to condemn this hate-fueled violence".