The Office of Film & Literature Classification has said it banned the Christchurch terrorist attack livestream because it was "clearly intended to record, share and glorify the acts of extreme violence and cruelty".
Chief Censor David Shanks officially banned the 16-minute and 55-second video last week, labelling it as "objectionable".
"The video promotes and supports the infliction of extreme violence and cruelty," the decision summary said.
"The video is clearly intended to record, share and glorify the acts of extreme violence and cruelty, namely the graphic mass murder of unsuspecting victims who are powerless to resist," he said.
Fifty people were killed and 50 others were injured at the attacks on Al Noor Mosque and the Linwood Islamic Centre on March 15.