Online accounts linked to 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 footage on Facebook of the attack on one of the mosques. Police later said four people, who they did not identify, were in custody and one had been charged with murder over the country’s worst ever mass shooting.

On Wednesday, 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, featuring the names of others who had committed race- or religion-based killings; Cyrillic, Armenian and Georgian references to historical figures and events; and the phrase: “Here’s Your Migration Compact”.

Read more: Reuters