Throngs of anti-Wall Street demonstrators snarled traffic by blocking a downtown Los Angeles street on Thursday, and later pitched tents outside a bank tower before police advanced to make arrests.

Hundreds of protesters first marched through the Los Angeles financial district, chanting Occupy the Freeways, Occupy the U.S.A., and then a small group stood in a circle and held hands on a major downtown street, blocking it, before police advanced.

Throughout the day, at least 73 protesters were arrested in the city in separate marches and rallies downtown, with the largest number being taken into custody for trespassing outside a Bank of America tower, police said.

The Los Angeles march came as cities across the country have taken police action in recent days to dismantle protest camps set up as part of the Occupy movement against economic inequality and excesses of the financial system.

The march also coincided with a day of action that saw hundreds of people take to the streets of several U.S. cities, including New York, where at least 177 people were arrested, in rallies seen as a test of momentum of the Occupy Wall Street movement.

The Los Angeles protest took place a few blocks from where Occupy demonstrators have an encampment on the City Hall lawn.

I think we're all saying the same thing, but in a million different ways, said Good Jobs LA organizer Sandra Gonzalez, 42, in explaining the relationship between her group, which organized the march, and the nationwide Occupy protests.

Gonzalez was later arrested with 20 other protesters after they blocked a major street by holding hands and forming a circle around three tents, police said.

The protest did slow traffic on freeways surrounding Los Angeles, as police closed a major off-ramp due to the crowd.

One of the first people taken into custody in the protest was 81-year-old Bertha Jordan, who was wearing a T-shirt that read Arrest Wall Street Bankers and was among those who stood in the middle of a street.

I'm a senior citizen and I've been abused and misused, Jordan told reporters, before she was led away by police.

Later in the day, protesters marched to a Bank of America tower in downtown Los Angeles, where some set up tents on a plaza. A total of 47 protesters were arrested there, on grounds that are considered private property, police said.

The Los Angeles protest came hours after police in Northern California cleared away a protest camp from a plaza at the University of California, Berkeley where 5,000 people had gathered Tuesday night in an economic protest.

Meanwhile in Portland, hundreds of Occupy demonstrators gathered on a major bridge Thursday and some of them sat down. At least 36 people were arrested in that city, police spokesman Lieutenant Robert King said.

Police in Las Vegas arrested 21 protesters who sat down in the street outside a federal courthouse after, police said.

But in Phoenix, a planned occupation of the city's light rail system by Occupy protesters fizzled. Only 20 to 30 demonstrators showed up at three rail stations, said Diane D'Angelo, a spokeswoman for the local Occupy movement.

We think they were intimidated, Phoenix is a very conservative city, she said.