Occupy Wall Street protesters have clogged streets and tied up traffic around the United States to mark two months since the movement's birth and signal they aren't ready to quit despite the breakup of many of their encampments by police.

More than 300 people have been arrested, most of them in New York.

The mostly peaceful demonstrations took place Thursday in cities including Los Angeles, Las Vegas, Boston, Washington and Portland, Ore. Most of the arrests were for blocking streets.

More than 1,000 protesters gathered near the New York Stock Exchange and sat down in several intersections. Helmeted police officers broke up some of the gatherings. Operations at the stock market weren't disrupted.

A coalition of unions and progressive groups joined Occupy demonstrators in staging rallies at landmark bridges in several U.S. cities to protest joblessness.

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