Story highlights NEW: A total of 50 are arrested in two incidents in L.A., an officer says

A total of 50 are arrested in two incidents in L.A., an officer says A total of 245 people are arrested in New York, according to police

48 are arrested in 3 incidents in Portland, Oregon, say police

N.Y. authorities say that at least 6 police were hurt while on duty

Thousands of Occupy Wall Street demonstrators deluged New York on Thursday, a show of strength in the movement's original home that was echoed nationwide as part of a "mass day of action."

Scores were arrested in New York, and several police officers were reported injured, as protesters fanned out across the city moved toward Foley Square in Lower Manhattan and the Brooklyn Bridge.

By early Thursday evening, many had crossed the bridge -- the same place where more than 700 had been arrested last month -- chanting, "This is what democracy looks like -- This is what America looks like," according to the New York movement's official Twitter feed. This time, they marched in the pedestrian walkway, not blocking the roadway. Nearby, pro-Occupy slogans were projected onto one side of the Verizon Building.

Those in New York were not alone. Like-minded activists also took to the streets in all corners of the nation -- from Miami to Los Angeles to Portland, Oregon, to Boston -- marking two months since the activist effort aimed at the nation's wealthiest 1% began in Manhattan.

"I think the numbers have increased dramatically today," said New York protester Jo Robin. "Particularly after the raid, our message is being broadcast all over the world."

The group twice squared off against riot police in Zuccotti Park, where they'd been evicted two days earlier. They'd also engaged in several confrontations with police, leading to scores of arrests.

That includes 64 protesters -- wearing T-shirts with the figure "99%" prominently featured -- arrested at an early evening sit-in on Centre Street near Foley Square in lower Manhattan, a police spokesman said. (Earlier, police spokesmen and protest organizers had said -- incorrectly -- that 99 people were arrested in this same incident.)

In total, police said around 8 p.m. that a total of 245 people had been arrested around the city.

During a late afternoon press conference, Police Commissioner Ray Kelly said that at least seven police officers were hurt Thursday during exchanges with protesters.

Five of those officers were injured when a unidentified liquid was thrown on their faces, Kelly said, adding that the officers experienced a burning sensation and required hospitalization.

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Photos: Photos: Zuccotti Park protesters evicted Photos: Photos: Zuccotti Park protesters evicted Police evict Zuccotti Park protesters – Police moved in to New York's Zuccotti Park early Tuesday, November 15, surprising many Occupy Wall Street protesters who had camped there for almost two months. Hide Caption 1 of 8 Photos: Photos: Zuccotti Park protesters evicted Police evict Zuccotti Park protesters – Continuing concerns about public health and safety and the impact of the protests on nearby businesses, as well as the rights of others to use the park, prompted city officials to dismantle the camp, Mayor Michael Bloomberg said. Hide Caption 2 of 8 Photos: Photos: Zuccotti Park protesters evicted Police evict Zuccotti Park protesters – Police arrested more than 100 people, according to Deputy Police Commissioner Paul Browne. Hide Caption 3 of 8 Photos: Photos: Zuccotti Park protesters evicted Police evict Zuccotti Park protesters – An arrested protester screams from a police van Tuesday. Hide Caption 4 of 8 Photos: Photos: Zuccotti Park protesters evicted Police evict Zuccotti Park protesters – After they were forced to leave the park, several hundred protesters marched to Foley Square. Hide Caption 5 of 8 Photos: Photos: Zuccotti Park protesters evicted Police evict Zuccotti Park protesters – Workers clean up Zuccotti Park on Tuesday after protesters were removed. Hide Caption 6 of 8 Photos: Photos: Zuccotti Park protesters evicted Police evict Zuccotti Park protesters – Circumstances at the park had become "unbearable," Bloomberg said. Hide Caption 7 of 8 Photos: Photos: Zuccotti Park protesters evicted Police evict Zuccotti Park protesters – Protesters regroup in Foley Square on Tuesday morning. Hide Caption 8 of 8

And a 24-year-old police officer was injured when a star-shaped glass object was thrown at him, Mayor Michael Bloomberg told reporters during a visit to Bellevue Hospital Center where the officer was being treated.

It is not clear how many demonstrators have been injured during the clashes.

CNN and CNN affiliate New York One broadcast images of the exchanges, including video of one man -- whose face appeared to be covered in blood -- sitting near police who wielded shields and batons.

Authorities constructed barricades at Zuccotti Park, in front of the New York Stock Exchange and along Fifth Avenue in an apparent attempt to keep demonstrators off the roads and on pedestrian walkways.

Residents and workers near the New York Stock Exchange were required to flash identification cards as police cordoned off the area amid concerns that demonstrators would try to disrupt trading.

Earlier in the day, protesters lifted metal barricades that ringed Zuccotti Park, a former home-base for the movement, defying authorities and blocking traffic.

Bloomberg said the day's protests had "caused minimal disruptions to our city," he asserted that some demonstrators had "deliberately pursued violence."

In Lower Manhattan, CNN iReporter Alvaro Perez shot video showing protesters being pulled away by police, including one woman who appeared to be dragged by her jacket and backpack.

"I don't want to speculate on what happened in advance of that," police spokesman Paul Browne said of the incident.

He said the "big picture" of how police have handled demonstrations has so far been mostly positive.

"People were able to get to work" and "protesters were able to protest," Browne added.

Earlier, on CNN's "American Morning," Howard Wolfson, a New York City deputy mayor, vowed, "We'll make sure, if people want to peacefully protest, they have the right to." But, he added, "if people break the law, we'll have to deal with that."

"If they attempt to enter a building they're not allowed in, that's breaking the law. If they want to express their concerns about Wall Street, that's totally fine," he said.

While the city has come under fire from protesters and other critics for arrests and removing protesters from Zuccotti Park, Wolfson insisted that "we had to act" to stop illegal activity, such as drug use, and to eliminate fire hazards.

"This is a place where we honor the First Amendment," he added.

Still, the ouster from Zuccotti Park did not appear to stifle the New York protest effort. The group tried to sum up its intent on a Twitter post: "Enough of this economy that exploits and divides us. It's time we put an end to Wall Street's reign of terror and begin building an economy that works for all."

The Occupy movement, likewise, showed few signs of abating elsewhere in the United States.

In cities such as St. Louis, Milwaukee and elsewhere, thousands responded to the "day of action" plea.

And as in New York, some of those ended up behind bars after refusing to heed law enforcement officers' calls to move.

The next highest arrest figure was in Los Angeles, where 25 people were arrested early Thursday and another 25 were arrested later in the day, Officer Andrew Neiman said. Bail was set at $5,000 for those detained, he added.

In Portland, police reported 48 people arrested in three separate incidents. That includes 25 taken into custody on the east end of the Steel Bridge, nine inside a Wells Fargo bank and 14 in and around a Chase Bank. In the latter incident on Thursday evening, Sgt. Pete Simpson said that police used pepper spray to get individuals to move off a street and from the path of a commuter rail line.

Another 21 were issued citations for blocking Las Vegas Boulevard in that Nevada city, Las Vegas police officer Bill Cassell told CNN, while Atlanta police arrested eight for blocking a roadway. There were also arrests in other places, including Los Angeles, Chicago and Houston.

And in Denver, District Attorney Mitchell Morrissey announced Thursday that three men now face felony charges -- including inciting a riot and assaulting a police officer -- for their alleged actions while clashing with authorities during Occupy Denver protests.