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Occupy Wall Street protesters, dressed as billionaires, stage a demonstration against Republican presidential candidate Mitt Romney in front of the Waldorf Astoria hotel as Romney holds a campaign fundraiser inside the hotel.

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A man distributes flyers on Wall Street, adjacent to the New York Stock Exchange, for an Occupy Wall Street event on May Day.

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Occupy Wall Street participants stage a march as part of May Day.

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Protesters briefly occupy a Vietnam Memorial park in lower Manhattan in New York City. Occupy Wall Street joined with unions during the May Day protests, a traditional day of global protests in sympathy with unions and leftist politics.

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Protesters hold a rally inside the Tom Bradley terminal of Los Angeles International Aiport during a May Day march in Calif. Workers at the airport went on a one-day general strike to protest what labor activists are calling unfair practices by airlines using hired contractors instead of unionized employees.

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Joann Trudeau joins in a May Day protest in Chicago, Ill. About 1,000 people joined in the march that went for two miles from the city's West side, into the Loop.

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A police lieutenant swings a baton at an activist in New York.

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A protester gestures during a rally for International Worker's Day outside the Alameda County Court House in Oakland, Calif.

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Ronald Schupp protests in front of police during a May Day march in Chicago, Ill.

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A protester holds a rose in front of Oakland police officers in Calif.

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Occupy LA supporters congregate in Pershing Square after participating in a march marking the International Worker's Day in downtown Los Angeles, Calif.