Warning: This article contains details that may disturb some people.
Snipers, sniffer dogs and armed police were stationed outside Christchurch's justice precinct on Monday as Brenton Harrison Tarrant appeared in the High Court.
The 29-year-old Australian mass murderer and terrorist was seated at a small desk inside the dock behind a 1.5-metre-high pane of thick glass and surrounded by five Corrections officers.
On Monday he was sentenced for 51 charges of murder, 40 of attempted murder and one of carrying out an act of terrorism for the attack on two Christchurch mosques in March 2019.
The Court heard how Tarrant obtained a firearms license in 2017 and began collecting high powered firearms and honing his weapons at local rifle clubs.
He also purchased in excess of 7000 rounds of ammunition.
In the months before the attacks he visited Al Noor Mosque, making detailed notes and flying a drone over the property, the court heard.
On the morning of March 15 he drove from his Dunedin home to Christchurch in a vehicle filled with firearms, ammunition preloaded into magazines, and four modified petrol containers intended for use as incendiary devices.
His intention was to burn down the mosques at the conclusion of the attacks.
The court heard how the gunman, parked near Al Noor Mosque, contacted his family before putting on a tactical vest, played loud music over the speaker and then began the attack.
In the following minutes Tarrant fired hundreds of shots at defenceless worshippers as they tried to flee the Christchurch mosques.
A total of 44 people died at the Al Noor Mosque as a direct result of his actions.
The Christchurch High Court heard the bravery of one worshipper, Naeem Rashid, who ran at the gunman and knocked him to his knee after being shot in the shoulder.
Rashid's actions allowed a number of worshippers to escape.
But across town at Linwood Mosque the terror continued. A total of seven people at the Linwood Islamic Centre died as a direct result of Tarrant's actions.
Altogether the attacks saw 51 dead and scores of others injured, and hundreds of lives changed forever from the terror of one man.