(CNN) The possession and distribution of a manifesto believed to be written by the suspect behind the Christchurch mosque attack is now illegal in New Zealand, officials said.

The Office of Film and Literature Classification announced Saturday that the document is objectionable under the law.

The so-called "manifesto" of Brenton Tarrant, the 28-year-old Australian charged with the murders of 50 people, spans more than 80 pages and is filled with anti-immigrant and anti-Muslim screeds.

"There is an important distinction to be made between 'hate speech,' which may be rejected by many right-thinking people, but which is legal to express, and this type of publication, which is deliberately constructed to inspire further murder and terrorism," said New Zealand's Chief Censor David Shanks.

"It crosses the line."

Read More