Dozens of cities across the world - from Tokyo to Alaska via London, Frankfurt and Washington - are holding demonstrations in a show of solidarity with the rallies that began last month in New York's financial district.
"On October 15, people from all over the world will take to the streets and squares ... to initiate the global change we want," proclaimed the website United for #GlobalChange.
"We will peacefully demonstrate, talk and organize until we make it happen. It's time for us to unite; it's time for them to listen."
New York protest
About 2,000 protesters marched through New York's financial district on Saturday afternoon, ahead of a planned rally in Times Square.
The demonstrators in lower Manhattan banged drums and chanted "We got sold out, banks got bailed out," "All day, all week, occupy Wall Street," and "Hey hey, ho ho, corporate greed has got to go."
Protests were also held elsewhere in the United States and Canada, notably in Washington DC, the US capital.
Meanwhile, in Berlin, around 4,000 people marched through the streets, with banners that urged the end of capitalism. Some marchers scuffled with police as they tried to get near the country's parliamentary buildings.
In Frankfurt, continental Europe's financial capital, about 5,000 people protested in front of the European Central Bank.
Outside London's iconic St Paul's cathedral, Wikileaks founder Julian Assange spoke to about 500 demonstrators.
"The banking system in London is the recipient of corrupt money," he said, adding that Wikileaks would launch a campaign against financial institutions in the coming months.
Scuffles broke out in the UK capital between police and protesters, who raised banners saying "Strike back!"; "No cuts!" and "Goldman Sachs is the work of the devil!"
In the Bosnian city of Sarajevo, hundreds walked through the streets carrying pictures of Che Guevara and old communist flags that read "Death to capitalism, freedom to the people."
Another 500 people gathered to hear speakers denounce capitalism at a peaceful rally in downtown Stockholm, holding up red flags and banners that read "We are the 99 per cent" and "We refuse to pay for capitalism's crisis."
The reference was to the world's richest one per cent, who control billions in assets, while billions around the world live in poverty or are struggling economically.
In Spain, groups that became known as the Indignant Movement established the first around-the-clock "occupation" protest camps in cities and towns across the country beginning in May and lasting for weeks. Six marches are set to converge Saturday on Madrid's Puerta del Sol plaza just before dusk.
Tens of thousands of Portuguese, angry at their government's handling of the economic crisis, also took to the streets of Lisbon. Portugal is one of three European nations - the others being Greece and Ireland - that have already needed an international bailout.
A group of 100 prominent authors, including Salman Rushdie, Neil Gaiman and Pulitzer Prize-winning novelists Jennifer Egan and Michael Cunningham, signed an online petition declaring their support for "Occupy Wall Street and the Occupy Movement around the world."
Other protests were staged in Geneva, Amsterdam, Athens, Brussels, Geneva, Paris and Zurich.
Melbourne, Australia's second-largest city, saw the day's first demonstration, when at least 1,000 people, including children, gathered at City Square.
"We face similar problems with our democracy here in Victoria and Australia as people face in most other developed nations," the Occupy Melbourne website said. "Our democracy is unwell."
In Sydney, about 2,000 protesters including representatives of Aboriginal groups, communists and trade unionists, protested outside the central Reserve Bank of Australia, at Martin Place in the central business district time.
Demonstrations of various sizes took place in Asia, namely in Japan's Tokyo, the Philippines' Manila, Taiwan's Taipei, South Korea's Seoul and China's Hong Kong.
Several protests and rallies were held simultaneously in various locations at the Japanese capital.
Hundreds of demonstrators marched to the headquarters of Tokyo Electric Power Co. and the Ministry of Economy, Trade and Industry to show dissatisfaction over the handling of the nuclear disaster triggered by the March 11 earthquake and tsunami.
Despite heavy rains in Seoul, the South Korean capital, members of more than 30 civic groups congregated outside the Financial Services Commission in Yeouido, the city's financial district.
Activists wearing Guy Fawkes masks staged performances to express their frustration with the growing income gap in Seoul, and chanted "We are the 99 per cent" - one of the seminal slogans of the Wall Street movement.
In Manila, about 100 members of Bayan, an alliance of various left-wing groups in the Philippines, marched to the US embassy, waving banners that read: "Down with US imperialism" and "Philippines not for sale", broadcaster APTN reported.
They were voicing support for the New York movement and expressed their criticism of US troop presence in the country's south.
One man was seen carrying a placard that read: "Genuine people's democracy lives in the streets."
In Hong Kong, more than 200 people gathered at Exchange Square Podium in the city’s central shopping and business district.
Some pitched tents to stay overnight at the site while others later migrated to the HSBC building nearby.
Taipei, the Taiwanese capital, saw a smaller turnout of near 100 people than the expected 1,500, at the city's landmark skyscraper Taipei 101, home to the Taiwan Stock Exchange.
The Occupy South Africa website announced "Operation Ubuntu", a Nguni word used to describe unity for a common purpose through an African worldview that people can only find fulfilment through interacting with other peoples.
Protests were scheduled in the country's major cities of Capetown, East London, Durban and Johannesburg for later on Saturday.
Greek protesters aligned with Spain's "Indignant" movement called an anti-austerity rally in Athens' Syntagma square, the focal point of many demonstrations during Greece's financial meltdown.
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