Hundreds of people protested at anti-monarchy rallies across Australia on Thursday, as the country observed a national day of mourning for the late Queen Elizabeth II.
The government declared Thursday a nationwide public holiday.
A national memorial service was held in Canberra and attended by Prime Minister Anthony Albanese and Governor-General David Hurley, King Charles III's representative in Australia.
Both had returned Wednesday from the queen's funeral in London.
The holiday has been marked by some protests that focused on the harm British colonisation caused indigenous Australians.
Australia is one of the few former British colonies that never struck a treaty with the indigenous population.
The government plans to change the Australian constitution with a referendum that would create a mechanism for indigenous people to consult parliament about policies that affect their lives.
The Warriors of the Aboriginal Resistance were one of the organisers of a protest in Melbourne, where demonstrators held signs that read “Abolish the monarchy" and "Black Lives Matter".
During the protest, the group called for an end to "racist colonial imperialism and its continuing effects" on Aboriginal and Torres Strait Islander peoples, who represent around 3.3% of Australia’s population.
Two opinion polls published since the queen's death show most Australians want to remain a constitutional monarchy.
Advocates for an Australian republic argue that this is a temporary reaction to the intense media coverage of a popular monarch.