Thousands of demonstrators have marched across New York's Brooklyn Bridge in one of several US rallies of support for the Occupy Wall Street movement.
Some 250 people were arrested in New York alone, many of them as trouble flared near the stock exchange.
Protesters accused police of brutality, with TV images showing a man with a bloodied face being arrested. At least seven police officers were hurt.
The rallies marked two months since the movement against inequality began.
The march was planned before demonstrators were swept two days ago from New York's Zuccotti Park, where they had camped since mid-September.
As darkness fell on Thursday evening, protesters - their numbers swelled by union activists - moved on to the Brooklyn Bridge.
Police arrested 65 of them who walked on to the bridge roadway, but otherwise let them pass on the pedestrian walkway.
Demonstrators massed earlier nearby in lower Manhattan's Foley Square, where their chants boomed off the surrounding government buildings.
Police tried to pen the protesters using barricades, but without success.
"This is a critical moment," demonstrator Paul Knick, a software engineer, told AP news agency.
"It seems like there's a concerted effort to stop the movement, and I'm here to make sure that doesn't happen."
Demonstrators had signs with "Police Brutality" written on them - a reference to police officers in riot gear dispersing protesters earlier in the week.
But after visiting a police officer who needed 20 stitches on his hand, New York Mayor Michael Bloomberg said: "If anyone's actions cross the line and threaten the health and safety of others including our first responders, we will respond accordingly."
Seven officers and 10 protesters were injured during the day, the New York Times reported.
In rallies across the US on Thursday:
- In Los Angeles about about 500 marchers chanted anti-bank slogans; more than two dozen were arrested
- City officials in Dallas evicted a protesters' camp, detaining nearly 20 people
- Arrests were made in Portland, Oregon, as activists tried to "occupy" a city centre Wells Fargo bank branch
- Dozens more demonstrators were held by police in Las Vegas, Nevada and St Louis, Missouri
- Protesters shut the river bridge in Chicago, Illinois during rush hour, while activists in Seattle, Washington closed the University Bridge
- Rallies were held at bridges considered in disrepair in Miami, Florida; Detroit, Michigan; and Boston, Massachusetts, as activists called for infrastructure projects to create jobs
- There were smaller protests elsewhere, including in Denver, Colorado and Washington DC
The day's events began with hundreds of demonstrators gathering at the edge of New York's financial district.
They were unable to get past junctions blocked by police, and as scuffles broke out some of them were dragged away by officers.
Some onlookers applauded the demonstrators from open windows, while others called out: "Get a job!"
Among those held in New York was a retired Philadelphia police captain, Ray Lewis, who was taken into custody in his dress uniform, amid cheers.
Some people were arrested after they sat down at an intersection, while others were detained as they tried to get closer to the stock exchange. Trading was not disrupted.
Frustrations boiled over in Zuccotti Park, the cradle of the nationwide movement, as hundreds of people tried to remove barricades surrounding the area and scuffled with baton-wielding officers.
A number of protester encampments have been removed in US cities in recent days.
Scores of arrests were made as police cleared tents in Oakland, California and Burlington, Vermont.
But evictions went peacefully elsewhere, including Atlanta, Georgia; Portland, Oregon; and Salt Lake City, Utah.