Police raided a 42-year-old man's Burnside house on March 25 "in relation to the Christchurch terror attacks" just 10 days earlier.
Officers seized his cellphone, on which the police digital forensic unit found numerous pictures and videos of the footage of the mosque attack, along with four copies of the alleged gunman's so-called "manifesto" – items that have been classified as objectionable.
A screenshot of the shooting was also found on the phone of the man who has interim name suppression with the text "Call of Duty Black Mosque NZ Edition" overlaid.
It shows the shooter holding an automatic rifle at the entrance to Al Noor Masjid and a deceased person lying in the entrance way, according to the police summary of facts.
"This newly-made image was then sent multiple times via Facebook Messenger with three laugh/cry emojis following one of the messages," police told the Christchurch District Court.
The defendant also used mobile phone video editing application YouCut to edit the original 16 minute, 55 second video into smaller files.
They were saved on the evening of March 17 – two days after the attack – and that night emailed eight times – four to one man, and another four to Arps.
When spoken to by police, the man admitted the offending and today pleaded guilty before Judge Stephen O'Driscoll.
He was remanded on bail to be sentenced on February 26.
Arps, 44, who thought graphic and banned footage of the Al Noor Mosque attack on March 15 was "awesome", was jailed for 21 months at Christchurch District Court in June after admitting two charges of distributing an objectionable publication.
Judge O'Driscoll said Arps, who owns a white supremacist-themed insulation company, had "glorified" the killings and showed "particular cruelty" and callousness.
Arps has appealed his sentence to the Court of Appeal, arguing that it was "manifestly excessive".
In 2016, Arps was one of a group of men who filmed themselves doing Hitler salutes as they delivered boxes of pigs heads and offal to the Al Noor mosque in Christchurch.
"White power ... Bring on the cull," Arps was seen saying in the video.
In that case, he was convicted of offensive behaviour and fined $800.
