New Zealand's Prime Minister Jacinda Ardern introduced a new bill to Parliament on Friday that aims to further tighten gun laws, and the country marked six months since a mass shooting in Christchurch that killed 51 Muslim worshippers.

This is New Zealand's second set of gun reforms, after weak firearm laws were identified as a key reason why a suspected white supremacist was able to own semi-automatic weapons that he used to kill people gathered at two mosques for Friday prayers on March 15.

Australian Brenton Tarrant has been charged for the attack and has pleaded not guilty.