A number of online anarchist groups have emerged, threatening to hold violent protests before and during next month's G20 summit in Brisbane. The news comes as authorities announced plans for a 24-hour court to deal with the expected mass arrests. Numerous groups have launched online campaigns threatening violence, with one saying that vandalism is 'not violent protest'. Scroll down for video Roads closures near the Brisbane Convention Centre, which will host the G20 Australia summit next month. Police planned a 24 hour special court in Brisbane for potential mass arrests from protests during the event Protesters smash police vehicles in Toronto's during the G20 summit protests in 2010. Australian activist groups are planning violent demonstrations in their online campaigns
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Local activist factions are planning violent protests
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An activist medic team has launched to treat  protesters on site
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Police have planned a 24 hour special court in Brisbane
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Experts believe notorious international groups such as Black Bloc could be mobilising for the event
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G20 meetings have been met with large scale riots in the past
A shattered glass-plate window cascades down as violent anti G20 protesters loot stores in T@placeholder