Prime Minister Jacinda Ardern announced on Monday (March 18) plans to tighten gun laws in light of the slaughter on Friday of 50 Muslim worshippers. She also encouraged owners to surrender unnecessary firearms after it emerged that the accused mosque attacker, Australia white nationalist Brenton Tarrant, had legally acquired the guns he used in the rampage. Ardern has said that details of the government's proposed legal changes on gun ownership will be announced by next week, indicating that gun buybacks and a ban on some semi-automatic rifles were under consideration.