Wearing a white prison suit, Tarrant appeared handcuffed and barefoot.
He flashed an upside-down "okay" signal, a symbol used by white power groups across the globe.
After Tarrant left, the judge said that while "there is one charge of murder brought at the moment, it is reasonable to assume that there will be others".
Tarrant was remanded without a plea until his next scheduled appearance in the South Island city's High Court on April 5.
An imam who was leading prayers at a Christchurch mosque when a gunman brandishing semi-automatic weapons mowed down his congregation said on Saturday (March 16) that the Muslim community's love for New Zealand would not be shaken by the massacre.
New Zealand police said 49 people were killed and 42 were being treated for wounds, including a four-year-old child.
Before Friday's attack, New Zealand's deadliest shooting in modern history took place in 1990 in the small town of Aramoana, where a gunman killed 13 people following a dispute with a neighbour.
While there was no reason to believe there were any more suspects, Ardern said the national security threat level was being raised from low to high, the second-highest level.
Prime Minister Jacinda Ardern said the events in Christchurch represented "an extraordinary and unprecedented act of violence", and that numerous victims could be migrants or refugees.
"The University of Toronto community has reacted with horror and sorrow on hearing of the terrorist atrocities committed against Muslims in Christchurch, New Zealand yesterday", U of T President Meric Gertlersaid on Friday.
Labelling the attack as an act of terrorism, New Zealand Prime Minister Jacinda Ardern has vowed to reform the country's gun laws. Many, such as the alt-right, are hidden in plain sight, with their proponents given a platform on social media websites - including Facebook, on which one of the terrorists in New Zealandlive-streamed his rampage - as well as mainstream Western news outlets.
"A category-A firearm holder can purchase the firearms without the magazines or the things that will enable them to be in the state that they were", Bush said.
The visiting Bangladesh cricket team was arriving for prayers at one of the mosques when the shooting started but all members were safe, a team coach told Reuters.
Western leaders from Donald Trump to Theresa May expressed solidarity with New Zealanders, deploring what the White House called a "vicious act of hate". He said he and others escaped by breaking through a glass door. "I don't understand how anyone could do this to these people, to anyone".
Yet the suspect himself highlighted New Zealand's remoteness as a reason he chose it. Children's screams can be heard in the distance as he returns to his auto to get another rifle. Vehicles are prohibited, but people can walk closer to the mosques where the shooting happened on Friday.
The weapons had been modified to allow the quicker discharge of rounds, she said. The singer bellows, "I am the god of hellfire!" and the gunman drives away. He also apparently smirked at photographers, according to the New Zealand Herald.
His manifesto was a welter of often politically contradictory views, touching on numerous most combustible issues of the day, among them the Second Amendment right to own guns, Muslim immigration, terrorist attacks and the wealthiest 1 per cent.
Raiders Cut A.J. McCarron, Jordy Nelson
Nelson was the Raiders' No. 1 wide receiver at the end of last season, and the team paid him a $3.6 million bonus late in 2018. The only other quarterback employed by the Raiders is Nathan Peterman , who's signed to a reserve/future contract.