Thousands of Occupy Wall Street protesters overtook the Brooklyn Bridge on Thursday night, as they continued demonstrations staged in New York City earlier in the day.

The Brooklyn Bridge takeover remained mostly peaceful. By 4 p.m., a crowd of 1,000 people, many of which representing labor union workers, began to march from Union Square to Foley Square in lower Manhattan. By 6 p.m., the crowd had swelled to an estimated 3,000. New York City Police eventually blocked off the entrance to the bridge and protesters on the Manhattan-side were pinned between barricades. Those who had crossed over and into Brooklyn continued to march to Cadman Plaza Park, chanting, "We are the 99 percent," as they went.

On Twitter, protesters shared their accounts of the action under the hashtags “#ows” and “#n17." One user wrote from the Brooklyn Bridge: “The last time #ows was on the Brooklyn Bridge they were arrested. Now back with 10 times the people. We are not scared. #n17.” In October, an estimated 700 protesters were arrested after a march on the same bridge.

As many as 300 people were arrested on Thursday in New York City alone, in what the Occupy movement hailed as a worldwide “Day of Action” that marked the two-month anniversary since the protests first began in downtown Manhattan. Seven police officers were taken in for medical treatment, including five who were doused with what was believed to be vinegar and one whose hand was cut by a flying piece of glass.

Earlier on Thursday, Occupy Wall Street protesters clogged downtown Manhattan streets, clashing with police and blocking access to the New York Stock Exchange. Official reports said that nearly 75 people were arrested during the morning’s protests, mostly for disorderly conduct and resisting arrest, however, OWS claims that over 200 were arrested by early afternoon. Reports of police brutality also marred the day's protests with news cameras capturing NYPD officers dragging one woman through the street by her hair before arresting her.

Activities began early Thursday morning when the group gathered in Manhattan’s Liberty Square to serve breakfast and share stories “of people on the frontlines of economic injustice.” But the intensity of the protests rose by 9:20 a.m. when the group succeeded in blocking off all access points to the New York Stock Exchange, nearly delaying the start of the opening bell.

Commuters reported delays on bridges and major roads into the city as many tried to avoid traffic from the protesters.

According to the group, their mission for the day is to “shut down Wall Street and occupy all of New York City with our bodies, voices and ideas.”

“We will no longer tolerate the oppression of the one percent who do not want to see a creative movement, based on inclusiveness and tolerance, triumph over a system deeply rooted in social inequality.” the group said on its website.

The Day of Action comes just two days after the group was evicted from their makeshift headquarters in Zuccotti Park. Camped out protesters were forced from the grounds when New York City Mayor Michael Bloomberg ordered the park cleaned after he and the park’s ownership expressed concerns over safety and sanitary conditions at the park. Although the mayor promised protesters they would be able to return, he noted that tents, backpacks and tarps would be prohibited. Following the announcement, Occupy Wall Street challenged the move, obtaining a court order enjoining the mayor from enforcing the restrictive policy. In a turn of events, however, the court order was overturned by a state Supreme Court judge late Thursday, resulting in the group being unable to re-settle at the park.

In addition to the New York protests, Occupy movements in other cities and several countries around the world are staging similar demonstrations to commemorate the anniversary. In Los Angeles, 500 Occupy L.A. demonstrators marched downtown near the city’s banking institutions, and in Portland police shut down a bridge in anticipation of a planned march by Occupy protesters.

(Photo: Mike Segar/Reuters)