Judge Paul Kellar allowed journalists to use cameras and shoot video but said Tarrant's face must be obscured in order to protect his right to a fair trial.
Condemning the terror strike, Ardern had described it as a "terror attack" and said it "appears to have been well planned".
"Hi guys how are you". The courtroom was closed to the public because of the heightened security risk.
Indonesian-born aeronautical engineer Lilik Abdul Hamid and a refugee from Afghanistan, Daoud Nabi, were among the victims.
Muslims hold placards after a prayer meet for victims of Friday's mosque attacks in New Zealand, outside a mosque in Jammu March 16, 2019.
The critically wounded four-year-old child was named as Elin by her uncle Sabri Daraghmeh, who told reporters in a phone call from Jordan on Saturday that she remains "in the danger phase".
On Facebook, a user named Alta Marie said her husband Zulfirman Syah and her son were both shot at the Linwood Mosque.
The video of Ardern's press conference in Wellington was published online by local broadcaster.
It is customary in Islam to bury the dead within the 24 hours.
When asked what he thought of the prime minister suggesting there should be a change in New Zealand's gun laws, the police commissioner said he was "happy to hear" that.
Feature: Terror suspect in New Zealand Christchurch mosques attack appears in court with heightened security - Xinhua | English.news.cn
Ardern said the suspect was a licensed gun owner who bought the five guns used in the crimes legally.
At least one of the weapons used by Tarrant was reportedly an AR-15 - the same semi-automatic rifle used in a number of mass shootings in the United States, including the 2012 Sandy Hook school killings in CT.
Armed police were deployed at several locations in all cities, unusual in a country where levels of gun violence are low. Story continues after video.
"Any loss of life at the hands of extremists regardless of religion, race or colour should be condemned in the strongest of terms".
"We need to ban some semi-automatics, perhaps all of them", he clarified.
Imran had dropped off his father, an electrical engineer, at the Al Noor mosque on Friday and was looking for a parking space when the shooting began.
Leaders around the world expressed sorrow and disgust at the attacks, with some deploring the demonisation of Muslims.
Ardern said she had spoken with Trump, who asked how he could help. "My message was sympathy and love for all Muslim communities", she said she told him.
Cook Islands prime minister Herny Puna said his country's prayers first and foremost were with the victims of the shooting, "their families, friends and loved ones whe are now faced with the irreconcilable loss of their loved ones". "New Zealand is home for all of us, and this despicable act will not change that feeling of closeness in us".More news: Police in Brick arrest accused killer of reputed mob boss
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