The Port Arthur massacre occurred on April 28–29, 1996, in the historic tourist town of Port Arthur in Tasmania, Australia. A 28-year-old lone gunman, Martin Bryant, murdered 35 people and injured 23 others using semi-automatic rifles. The rampage began at a local guest house where Bryant killed the owners, before he moved to the Port Arthur historic site, opening fire inside a crowded café, a gift shop, and the surrounding grounds.
Bryant was captured by police the following morning after an overnight standoff at the guest house.

The tragedy stands as the worst mass shooting in modern Australian history and profoundly shocked the nation.
In the immediate aftermath, the federal government, led by newly elected Prime Minister John Howard, took decisive action to prevent future atrocities. Working with state governments, the administration introduced the National Firearms Agreement (NFA), which implemented some of the strictest gun control laws in the world.

The NFA instituted a comprehensive ban on all automatic and semi-automatic long firearms, established a national firearm registry, and mandated strict licensing requirements based on a "genuine reason" for gun ownership (explicitly excluding personal protection).
To remove these weapons from circulation, the government enacted a mandatory national gun buyback scheme, which resulted in the surrender and destruction of roughly 650,000 newly prohibited firearms.

The swift legislative response drastically altered Australia's gun culture and remains a global benchmark for firearm regulation reform.