The alleged Christchurch mosque killer's banned manifesto has been booby-trapped online by hackers.

The so-called "manifesto", reportedly written by the alleged murderer of 50 Muslim worshippers at Friday prayer on March 15, has been officially classified as objectionable by the Office of Film & Literature Classification in New Zealand.

Chief censor David Shanks has urged anyone with copies of the "crude booklet that promotes murder and terrorism" to destroy them.

Despite the ban, however, and it being removed from the various sites it was initially posted to, copies have continued to circulate on dark avenues of the internet and social media sites.

But now, an online vigilante using the name "Māori" is circulating a "weaponised" version of the document in an apparent attempt to thwart its distribution.

When it's clicked on, it forces a system reboot that ends with a black screen featuring a message in red writing: "This is not us!"

The hacked version was discovered by security firm Blue Hexagon, which has dubbed the hack "Trojan Haka".

"Our initial suspicion was that this was targeting the press, but with all the data that we have now, it looks like it was not one specific group, just anyone who was trying to get a copy of the manifesto," Blue Hexagon researcher Irfan Asrar told PCMag.

The document, examined under the Films, Videos & Publications Classification Act 1993 (FVPCA), is deemed objectionable for a number of reasons.

"It promotes, encourages and justifies acts of murder and terrorist violence against identified groups of people," Shanks said.

"It identifies specific places for potential attack in New Zealand, and refers to the means by which other types of attack may be carried out. It contains justifications for acts of tremendous cruelty, such as the deliberate killing of children.

"We have dealt with terrorist promotional material before which was deliberately designed to inspire, encourage and instruct other like-minded individuals to carry out further attacks. For example, we have found a number of ISIS publications to be objectionable in previous decisions. This publication falls in the same category."

It is an offence to possess or distribute an objectionable publication.

Since the March 15 terror attack, several people have been charged under Films Videos and Publications Classification Act and are going through the courts.

More information can be found here:

https://www.classificationoffice.govt.nz/news/latest-news/christchurch-attacks-press-releases/
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