New Zealand has criminalized the possession or distribution of the racist "supremacy of the white" concept associated with the attack on the Christchurch mosque, which killed 50 Muslims.

New York's Chief Superintendent David Shanks on Saturday formally named the 74-page statement written by the terrorist who carried out the bloody attack as "unacceptable" to "possess or distribute" the statement as criminal acts.

"Others have referred to this publication as a statement, but I consider it a blunt booklet that promotes murder and terrorism," Shanks said in a statement.

"There is an important difference to be made between the hate speech, which may be opposed by many right-wingers, but its expression is legal, and this kind of pamphlet, which was deliberately drafted to incite murder and terrorism," he said.

Minutes before the attack began, the terrorist released the statement on the Internet and e-mailed it to Prime Minister Jacinda Ardirne.

The killer during his appearance before the judiciary (Reuters)

Great alternative
In his statement entitled "The Great Alternative", the murderer explained the reasons for the massacre. He pointed to the large number of immigrants whom he considered to be occupiers and invaders. He also explained why he chose this particular mosque.

"Our land will not be a day for immigrants, and this country, which was for white men, will remain, and they will never be able to replace our people," he said.

He claimed that the massacre was in retaliation for the "hundreds of thousands of deaths caused by the invaders in European territory throughout history," adding "to avenge the thousands of enslaved Europeans who were taken from their lands to be enslaved by Muslims."

The killer, in his statement, was influenced by US President Donald Trump as "a symbol of the restoration of white identity."

The terrorist murderer said his attack was inspired by Anders Behring Brevik, the perpetrator of Norway's 2011 attacks. His crime was also alleged to have taken revenge for an attack in Sweden in April 2017 that killed a girl among his victims. He also said he was influenced by Canadis Owens, a pro-US activist.

He added that the period between April 2017 and May of the same year changed his view significantly, and after the Stockholm attack on 7 April 2017, "I can no longer turn my back on violence ... there was something different this time."