On March 15, 2019, Australian man Brenton Tarrant carried out an attack on the Al-Noor and Linwood Islamic Centre mosques, killing 51 worshippers and injuring 40, all while livestreaming.
Those mosques continue to be targeted, with Al-Noor Mosque Imam Fouda giving word in February of fresh threats "of hatred against places of worship", drawing police support.
"I urge individuals who sent this terrible message to reflect on their words and actions, and instead choose kindness and compassion," Mr Fouda said.
He has also sounded fears over a government pledge to review the Arms Act.
Semi-automatic weapons were all but banned by Jacinda Ardern's government in the aftermath of the attacks in a 119-1 vote of parliament.
The one opposition vote - the libertarian right-wing ACT party's David Seymour - has since grown his party to 11 MPs, and is now serving in government.
Among their ranks is Nicole McKee, a former Council of Licenced Firearms Owners spokeswoman, and now, the associate minister responsible for rewriting the laws.
Ms McKee argues law reform is necessary as the guns are already in New Zealand, and better laws would "increase compliance".
Mr Fouda is among those alarmed by the proposed changes, telling Christchurch paper The Press, they would be a "leap backwards".
"I was proud as a New Zealander when our government took the steps to change the law after the terrorist attacks on our communities," he said.
"I'm concerned that reintroducing semi-automatics will compromise public safety and increase the risk of similar incidents occurring in the future."
Prime Minister Chris Luxon will attend an official memorial service at Al-Noor. He has spent time with victims, police and first responders in Canterbury in the lead-up to the service, and has a personal link with the attack.
As Air New Zealand chief executive, he spent time with the family of an airline engineer Lilik Abdul Hamid, who was among those killed at Al Noor Mosque.
Mr Luxon said he would be canvassing the community for their views on the reforms.
"I spent a lot of time in Christchurch at that time immediately in the hours after the massacre as well," Mr Luxon said.
"I have a lot of sensitivity for the community, and I want to be able to sit down with them, in fairness, just privately, and to be able to have them raise their concerns with me."
This year's anniversary is also the first since research revealed the terrorist discussed his attacks online much earlier than first thought.
University of Auckland academic Chris Wilson and a team at his Hate & Extremism Insights Aotearoa (HEIA) organisation identified posts from the Australian on a notorious online message board which glorified violence and specifically mass killings, including school shootings.
"He advocated for and praised the sadistic and brutal killing of innocent civilians," Dr Wilson wrote.
"The key for Tarrant was that this violence was perpetrated by white men. For him, any white violence might trigger the race war and segregation he desired.
Dr Wilson said his findings showed "numerous opportunities" for security services to identify Tarrant and, potentially, stop the attack.
"What we found overturns a great deal of what we thought we knew about him," Dr Wilson wrote.
"It also raises serious questions, not only about why this posting was not detected before the attack, but also why it has not been discovered in the five years since the March 15 attacks."