Two armed guards brought Brenton Tarrant into court.
He was likely to face further charges, police said.
Self-professed fascist occasionally turned to look and smirked at media present in court during the brief hearing that was held behind closed doors for security reasons.
28-year-old terroris charged for murder in relation to the mosque attacks, is lead into the dock for his appearance in the Christchurch District Court, New Zealand March 16, 2019. BBC quoted witnesses saying that they ran for their lives and saw people bleeding on the ground outside the Al Noor mosque. In addition, 48 people have been injured and are now being treated at a Christchurch hospital.
Police took three men and a woman into custody.
"It's outrageous, the feeling is outrageous", he said.
New Zealand Prime Minister Jacinda Ardern has called the shootings an "unprecedented act of violence". The suspected attacker had bought five guns legally.
At least 49 people were killed Friday, and dozens more were injured, at the two mosques targeted in the attack.
The New Zealand Police note how the Arms Act of 1983 doesn't require gun license holders to register their specific firearms with the exception of any military style semi-automatic firearms, pistols or other restricted weapons.
"The offender was in possession of a gun license" obtained in November 2017, and he started purchasing the weapons the following month, she said.
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Australian Prime Minister Scott Morrison said one of the men in custody was Australian.
He is "sickened" that the shooter said to "subscribe to PewDiePie" in a video before the shooting. The remaining victim succumbed in hospital.
None of those arrested had a criminal history or was on any watchlist in New Zealand or Australia.
One man who said he was at the Al Noor mosque told media the gunman was white, blond and wearing a helmet and a bulletproof vest. "Some were covered in blood", he told AFP.
"Today we stand with the people of Christchurch, New Zealand".
Due to this, the number of firearms in New Zealand is largely unknown, although a May 2018 report by New Zealand police recorded approximately 254, 940 active firearm licences. Friday is Islam's holy day.
Below are four ways you can support the New Zealand shootings survivors and families of victims.
Two Indonesians, a father and son, were also among those shot and wounded, Foreign Ministry spokesman Arrmanatha Nasir said.
"There were bodies all over", he said. In fact, right now, I'm sure New Zealand would like me to share a message on their behalf too.
Meanwhile, the third cricket test between New Zealand and Bangladesh has been cancelled in the wake of the shooting.