The surrendered firearms have included weapons from the 1800s and World War I and II, part of a three-month amnesty allowing Australians to turn in unregistered guns without penalty.
This interactive map allows you to explore all the incidents of mass shootings in the US dating back to the 1980s.
In Brazil, where the homicide rate is five times higher than in the United States, politicians are debating a law to make it easier for residents, including convicted criminals, to buy guns. A group of conservative lawmakers wants to allow Brazilians to buy up to nine guns a year.
Media outlets have named the gunman who carried out the deadly shooting at the community college in Oregon. But the local sheriff has refused to do so saying he doesn't want to give the shooter the attention he likely craved.