Of the 50 wounded, 36 remain in hospital with 11 in a critical condition.
"But that arrest was tangential to this matter and we do not believe that he was involved in this attack either", he said.
A total of four people were arrested following the massacre - one of whom was in possession of a firearm but with the intention of assisting police, and was released a short time later.
The 28-year-old Australian man accused of yesterday's terror attack that left at least 49 people dead in Christchurch has appeared in court this morning, charged with murder.
Bishop of Polynesia - The Most Reverend Fereimi Cama said the Anglican Diocese of Polynesia unequivocally condemned this act of terrorism.
People have also been laying flowers outside of mosques in other parts of New Zealand in solidarity with the victims and their famlies. Facebook, Twitter and YouTube all said they had taken steps to remove copies of the videos.
Meanwhile, New Zealand's Prime Minister Jacinda Ardern said the suspect held a Category A gun licence which enabled him to legally obtain semi-automatic weapons.
Ardern noted that this individual traveled around the world and spent "sporadic periods of time" in New Zealand.
"That obviously leads to an Australian-based investigation and all of our inquiries here will be absolutely shared and communicated with New Zealand authorities".
An Afghan man, thought to be in his 60s or 70s, died after he reportedly ran into the line of fire to save fellow worshippers at the Al Noor mosque in central Christchurch.
A few hundred demonstrators have protested the New Zealand mosque shootings outside Istanbul's Hagia Sophia - a Byzantine-era cathedral that was turned into a mosque and now serves as a museum.
Police said three people were in custody including a man in his late 20s who's been charged with murder. "We do see gunshot wounds but 50 people in one day is more than what we should see", Robertson said a news conference.
The victims of Friday's shooting included immigrants from Jordan, Saudi Arabia, Turkey, Indonesia, and Malaysia. - AP Police stand by a collection of flowers near the Linwood Mosque in Christchurch, New Zealand, Saturday, March 16, 2019.
'Just 24 hours after the Christchurch shooting New Zealand bans semiautomatic guns!' she wrote in reference to New Zealand Attorney General David Parker's comments about banning the controversial weapons.
Brenton Tarrant used two semi-automatic weapons, two shotguns and a lever-action firearm in the attack. The minimum legal age to own a gun in New Zealand is 16, or 18 for military-style semi-automatic weapons.
"Just around the entrance door there were elderly people sitting there praying and he just started shooting at them", Mazharuddin told Sky. They have not heard from him since.
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 neighbor.