一个美国海军陆战队的VH - 60飞过黑鹰多伦多的金融区，超过联盟站徘徊在一个很低的高度，在下午一时于2010年6月23日，在高楼大厦之间。它降落在草地旁边的电视塔，为即将举 行的20国集团做过去的周末/演练空中试验。 （©陈大卫克）

对土地的组织后卫领导带领多伦多的街头，数百土著人民游行，提请注意在加拿大土著人民困境 两天2010年6月24日之前的20国集团首脑会议开幕游行在加拿大多伦多。 （松 树伯爵夫人/ Getty图像）

Protesters march during a demonstration for indigenous sovereignty ahead of the G8 and G20 summits in downtown Toronto, June 24, 2010. (REUTERS/Mark Blinch) #

Oxfam activists pose as G8 leaders "pregnant with promise" during a photo opportunity ahead of the G8/G20 summits in Huntsville, Ontario June 24, 2010. Oxfam urged the leaders to deliver their promises made in past G8 meetings. From left, portraying Italy's Prime Minister Silvio Berlusconi, Britain's Prime Minister David Cameron, U.S. President Barack Obama, Canada's PM Stephen Harper, German Chancellor Angela Merkel, France's President Nicolas Sarkozy, Russia's President Dmitry Medvedev and Japan's PM Naoto Kan. (REUTERS/Carlo Allegri) #

People sit in Muskoka-style chairs next to a "fake lake" inside the G20 International Media Centre on June 25, 2010 in Toronto, Canada. The $57,000 water feature, part of the larger Media Centre costing nearly $2 million, includes comfortable chairs for visiting journalists, canoes and a large video screen showing beautiful scenes of Canada. (Chip Somodevilla/Getty Images) #

A pedestrian crosses an empty Yonge street in Toronto on Friday, June 25, 2010. (AP Photo/The Canadian Press, Adrien Veczan) #

Heads of state and world leaders, walk to the 2010 G8 Summit family photo at the Deerhurst Resort in Huntsville, Ontario, Canada, Friday, June 25, 2010. From left are: Italian Prime Minister Silvio Berlusconi; EU President Jose Manuel Barroso; US President Barack Obama; German Chancellor Angela Merkel; French President Nicolas Sarkozy; President of the European Council, Herman Van Rompuy; Russian President Dmitry Medvedev; British Prime Minister David Cameron; and Canadian Prime Minister Stephen Harper. (AP Photo/Saul Loeb) #

Protester Jim Duncan demonstrates in the "designated free speech area" in Huntsville, Ontario, Canada on June 25th, 2010. Protest activity has been light during the G8 Summit, held in the small community north of Toronto. (Simon Hayter/Getty Images) #

Toronto Metro Police in riot gear prepare to deploy around G20 Summit protesters in midtown Toronto June 25, 2010. (REUTERS/Fred Thornhill) #

Protesters line the streets carrying signs and banners during the G20 summit in in Toronto June 26, 2010. (REUTERS/Mark Blinch) #

Police in riot gear stand guard in front of activists during a protest ahead of the G20 Summit in downtown Toronto, June 25, 2010. About 2,000 protesters thronged Toronto on Friday in the biggest rally yet against the G20 summit, facing off against police in riot gear just blocks from the U.S. consulate. (REUTERS/Mark Blinch) #

A police officer holds back demonstrators protesting the G8/G20 summits June 25, 2010 in Toronto, Ontario, Canada. (Scott Olson/Getty Images) #

A demonstrator dressed as a seal stands beside police officers dressed in riot gear during a protest ahead of the G20 Summit in downtown Toronto, June 25, 2010. (REUTERS/Mark Blinch) #

The Feminist March files down College St. on June 25, 2010 in Toronto, Ontario, Canada. The march was one of several planned in the city to coincide with the gathering of world leaders for the G20 and G8 summits being held in Toronto and nearby Muskoka June 25-27. (Jemal Countess/Getty Images) #

A police escort waits on the tarmac for the Prime Minister Recep Tayyip Erdogan of Turkey and his wife Emine Erdogan to arrive at Pearson International Airport for the G8 and G20 Summits, Friday, June 25, 2010 in Toronto. (AP Photo/Carolyn Kaster) #

Riot police on horseback move through the streets of downtown Toronto in the midst of protests against the G20 summit in Toronto, June 26, 2010. (REUTERS/Mark Blinch) #

A photographer takes pictures as police officers form a line to hold back demonstrators protesting the G8/G20 summits on June 26, 2010 in Toronto, Ontario Canada. (Scott Olson/Getty Images) #

A protester with a flower clenched in his teeth is seized by riot police during protests at the G8 and G20 Summits, Saturday, June 26, 2010, in Toronto. (AP Photo/Carolyn Kaster) #

A violent anti-G20 protester, using Black Bloc tactics, throws a chair through the window of a Tim Horton's while demonstrators smashed their way through downtown streets June 26, 2010 in Toronto, Canada. (Simon Hayter/Getty Images) #

Demonstrators attempt to stop some of the violent anti-G20 protesters, part of a group using Black Bloc tactics, from entering a shopping mall downtown June 26, 2010 in Toronto, Canada. (Simon Hayter/Getty Images) #

A violent anti-G20 protester, part of a group using Black Bloc tactics, threatens journalists downtown June 26, 2010 in Toronto, Canada. (Simon Hayter/Getty Images) #

A group of protesters all wearing black destroy a police car as the authorities stood nearby. June 26, 2010 in Toronto, Canada. (© Olivier PontBiand) #

An anti-G20 protester, part of a group using Black Bloc tactics, reaches into a store's broken window to loot cell phones downtown June 26, 2010 in Toronto, Canada. (Simon Hayter/Getty Images) #

The first of two Police squad cars was set on fire on Queen Street at Spadina Avenue, June 26, 2010 at 6:26pm. A second squad car 15 feet away was torched about an hour later and earlier in the day at around 3:30pm 2 squad cars were set on fire at King/Bay Street in Toronto. (© David G. Tran) #

Police officers in riot gear walk in front of a burning police car during a protest against the G20 summit in downtown Toronto, June 26, 2010. (REUTERS/Mark Blinch) #

Riot police, using tear gas, try to disperse demonstrators at Queens Park in Toronto, Saturday, June 26, 2010. (AP Photo/Gerry Broome) #

Police officers clash with protesters during a demonstration at the G20 summit in Toronto, June 26, 2010. (REUTERS/Christinne Muschi) #

A protester lies bleeding as he is detained by riot police during a demonstration against the G20 summit in Toronto, June 26, 2010. (REUTERS/Christinne Muschi) #

Police officers stand behind their bicycles as protesters are stopped by a line of officers behind a burnt police car during G20 Summit protests in downtown Toronto June 26, 2010. (REUTERS/ Mike Cassese) #

Police arrest a protester during an anti G20 demonstration on Saturday, June 26, 2010 in Toronto. (AP Photo/The Canadian Press,Ryan Remiorz) #

Protesters thought to be part of an anarchist group using black bloc tactics change from their black outfits into street clothes as police surround their position following their anti G20 rampage through the streets of Toronto, Canada, June 26, 2010. (GEOFF ROBINS/AFP/Getty Images) #

Police officers in full riot gear form a wall across Yonge Street June 26, 2010 in Toronto, Canada. (Chip Somodevilla/Getty Images) #

Marine One, with U.S. President Barack Obama and British Prime Minister David Cameron aboard, prepares to land alongside Toronto's CN Tower, following their flight from the G8 Summit to the G20 Summit, June 26, 2010. (REUTERS/Jason Reed) #

Heads of state and governments and other dignitaries pose for a family picture during the G20 summit on June 27, 2010 in Toronto. (ERIC FEFERBERG/AFP/Getty Images) #

French President Nicolas Sarkozy, right, Russian president Dmitri Medvedev, left, and German Chancellor Angela Merkel talk during their trilateral meeting on the sidelines of the G20 Summit inToronto Sunday, June 27, 2010. (AP Photo/Eric Feferberg) #

Police arrest a protester at a rally outside the temporary G20 police detention center, where over 500 people are now being detained on June 27, 2010 in Toronto, Ontario, Canada. Police ramped up arrests across the city after widespread violence and vandalism plagued the city on the first day of G20 Summit. (Jemal Countess/Getty Images) #

A photojournalist shows the damage done to his lower back by a rubber-coated bullet fired by riot police during the G20 Summit June 27, 2010 in Toronto, Canada. (Simon Hayter/Getty Images) #

Riot police push against a crowd during a street demonstration on the closing day of the G20 Summit in Toronto, Sunday, June 27, 2010. (AP Photo/Carolyn Kaster) #

Riot police in Toronto, Canada make a mass arrest in front of the Novotel Hotel June 26, 2010, where several of the G20 delegations are staying, as the police attempt to secure the city's downtown core near the summit site. Toronto police used tear gas and arrested 75 when a violent mob tried to hijack a peaceful protest by tens of thousands of people against the G20 summit here Saturday, the city's police chief said. (GEOFF ROBINS/AFP/Getty Images) #

Selena Flood (center) is embraced by friends Jeremy Fischer (left) and Seamus Parker after they were released from the temporary G20 detainment center June 27, 2010 in Toronto, Canada. Hundreds of people, including journalists, were arrested by police in downtown Toronto during the G20 Summit and many were released prior to the 24-hour limit at which time they had to be charged with a crime. (Simon Hayter/Getty Images)

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