Christchurch

ONLINE accounts linked to the gun attacks that killed 49 people and wounded at least 20 at two New Zealand mosques on Friday had in recent days circulated white supremacist imagery and extreme right-wing messages celebrating violence against Muslims and minorities on social media and message boards.

A gunman broadcast live on Facebook footage of the attack on one of the mosques. Police later said four people were in custody and one had been charged with murder following the country's worst mass shooting.

On Wednesday, someone with the Twitter handle @brentontarrant tweeted pictures of one of the guns later used in the mosque attacks in the city of Christchurch. It was covered in white lettering and featured the names of those who had committed race- or religion-based killings; it also had Cyrillic, Armenian and Georgian references to historical figures and events, and the phrase "Here's Your Migration Compact".

The number "14" was written on the side of the rifle as well, a reference to the "14 words", a white supremacist mantra.

Other tweets from the same user that day included references to declining white fertility rates, articles about right-wing extremists in various countries and stories about purported crimes by illegal immigrants.

The Twitter profile had 63 tweets, 218 followers and was created last month.

A person involved with the attacks also appeared to post regularly to the "/pol/ - Politically Incorrect" forum on 8chan, a online discussion site known for allowing virtually any content, including hate speech.

At about 1.30 pm (8.30 am Singapore time) on Friday, the anonymous user told the group: "I will carry out and attack against the invaders, and will even livestream the attack via Facebook".

The post drew approving responses in the form of Nazi images and memes; it also featured a link to a 74-page manifesto that said the user was motivated by "white genocide", a term white supremacists use to describe immigration and growth of minority populations. The post was also linked to a Facebook page of a user called brenton.tarrant.9, from where the attack was livestreamed.

The @brentontarrant Twitter account and the brenton.tarrant.9 Facebook page were suspended soon after the shooting.

Facebook tweeted: "Police alerted us to a video on Facebook shortly after the livestream commenced and we quickly removed both the shooter's Facebook and Instagram accounts and the video."

When the attack started on Friday, an anonymous 8chan user remarked: "actually happening. delete this thread now or its gonna be the end of 8pol". A few minutes later, another said: "this sounds fun". "Nice shootin Tex," another commented.

The Facebook livestream of the attack, apparently recorded with a head-mounted camera, began at about 1.40 pm local time.

As the attacker drove to the mosque, he played music, including a British grenadiers march and a Serbian anti-Muslim hate anthem called "Remove Kebab". Upon arrival in the Hagley Park district of Christchurch, he parked the car and opened the rear hatch, revealing a cache of guns, ammunition and what appeared to be red fuel containers.

Picking up two guns, he walked to the entrance of a mosque and began shooting. The livestream ended under 20 minutes later; he was arrested at about 3 pm.

"Do you feel any remorse for the attack"? the author asked self-referentially in the manifesto. "No. I only wish I could have killed more invaders, and more traitors as well." REUTERS