THOUSANDS of Australians demonstrated on the anniversary of Britain’s colonisation of their country today, with large crowds urging that Australia Day be moved and replaced by a day of mourning on the holiday many label “Invasion Day.”

The holiday marks the arrival of 11 British ships carrying convicts at Port Jackson in present-day Sydney on January 26 1788. 

Many activists say the day marked the beginning of a sustained period of discrimination and expulsion of Indigenous people from their land without a treaty.

Thousands of people, many of whom waved Indigenous flags, rallied in front of the Victoria state parliament in Melbourne, calling for an official day of mourning to be declared across Australia. Roads and tram lines were shut down for more than four hours.

Large crowds in Sydney chanted for the Australia Day date to be moved.

Thousands of protesters also rallied in Brisbane, and the second day of Australia's cricket match against the West Indies was briefly disrupted by demonstrators.

Major sports have stopped calling the holiday Australia Day, and the Australian Football League Players Association, as well as several clubs and hockey teams, have called for the date to change.

On Thursday, two monuments symbolising Australia’s brutal colonial past were damaged in Melbourne. 

A statue of British naval officer James Cook, who in 1770 charted Sydney’s coast, was sawn off at the ankles, and a monument to Queen Victoria was doused in red paint.

Aboriginal and Torres Strait Islander people make up around 3.8 per cent of Australia's population of 26 million; Indigenous people are the nation’s most disadvantaged ethnic minority.

Australian voters rejected a referendum in October to create an advocacy committee to offer advice to Parliament on policies that affect Indigenous people. 

Prime Minister Anthony Albanese said today that the national day was an opportunity for Australians to “pause and reflect on everything that we have achieved as a nation.”