Shockingly, Tarrant livestreamed the killings on Facebook from a GoPro camera he had previously attached to a helmet he wore during the attack. The livestream lasted for over 17 minutes, until Facebook moderators terminated the broadcast. The attack marked the worst mass murder in the history of New Zealand, and led to several new pieces of legislation, including strict gun control policies, which have since come into effect. Meanwhile, a manifesto that Tarrant wrote while planning his attack, titled “The Great Replacement”, has become wildly popular among neo-Nazi and other far-right circles worldwide.

According to revelations made public during Tarrant’s trial this week, the 29-year-old far-right militant planned his attacks for months, using sophisticated technology at every opportunity in the process. The prosecutors told the court that Tarrant made use of a commercially available drone to film the grounds of at least one of the mosques, which he later attacked. He allegedly used the drone footage to study the entry and exit points of the building and to carefully map his arrival and departure. He also made use of Internet applications and databases to study maps and the buildings themselves, as well as visuals of the insides of the mosques, prior to launching his attack. According to the prosecutors, Tarrant also studied Islamic religious customs and practices so as to ensure that the mosques would be packed with worshipers when he launched his armed assault.

According to the Australian Financial Review, which published this information, the use of technology by Tarrant to plan his attack was previously unknown to the public. It was revealed earlier this week in court, as prosecutors discussed it openly for the first time. Yesterday Tarrant was sentenced to life in prison without parole, becoming the first person in the history of New Zealand to receive such a sentence. Tarrant reportedly showed no emotion during the court proceedings.