The Australian man who opened fire inside two mosques in Christchurch, New Zealand, has pleaded guilty to 51 charges of murder, 40 counts of attempted murder and one count of engaging in a terrorist act. Details: Brenton Tarrant entered his changed plea via video link from Auckland Prison Thursday morning local time. New Zealand Police Commissioner Mike Bush said in a statement sentencing would not take place until all victims who wish to attend the hearing can do so. "Due to the COVID-19 epidemic that will not be possible for some time," he noted. Why it matters: The March 15, 2019 attacks resulted in the deaths of 51 people and led to sweeping reforms of New Zealand's gun laws, including a ban on military-style semi-automatic weapons and assault rifles and the introduction of a buyback scheme that resulted in more than 10,000 firearms being handed in.Facebook changed its policy on live-streaming video violations in response to the mosque shootings being broadcast on the social media site.Countries around the world have signed on to the Christchurch Call, an effort to reduce violent extremist content online that was launched by governments and tech companies. (The U.S. government has not signed on to measure, citing First Amendment concerns.)The big picture: The gunman originally pleaded not guilty last June. Justice Cameron Mander said in a statement the court received indication that from the defense counsel of the plea change earlier this week.Of note: New Zealand has reported 205 cases of the novel coronavirus and was placed under alert level 4 measures just before midnight Wednesday local time, which essentially place the country on lockdown.Mander said the 17 people who were allowed in court to hear the guilty plea, including the imams of the Linwood and Al Noor mosques, where the attacks took place, observed the physical distancing requirements of the alert level.What's next: The defendant has been further remanded in custody until May 1, "at which time the position will be reviewed and either a sentencing date will be set or there will be a further remand in custody," Bush said.Go deeper: Christchurch mosque attacks: Suspect charged with terrorismEditor's note: This article has been updated with new details throughout.