THE Occupy Wall Street movement demonstrated both its power and its potentially ugly side as demonstrators in the Californian city of Oakland shut down the fifth-busiest port in the US, before a night of violence that landed at least four protesters in hospital.
Oakland was last night getting slowly back to normal after anti-capitalist campaigners barricaded entrances to the harbour on Wednesday night to prevent shift workers getting to their jobs.
It was supposed to be the triumphant culmination of a day of marches and action that drew 7,000 people, one of the largest events in the seven-week-old movement that began in the US financial capital, New York, and has spawned copycats across the US and around the world.
Oakland has become a focal point for the movement, not just to protest inequality but also to protect the right to peaceful protest.
It was in Oakland last week that an Iraq war veteran, Scott Olsen, was hospitalised with injuries from a police projectile during a heavy-handed attempt to clear the city centre of its protest camp.
Demonstrators who were still on the streets in the early hours of yesterday morning were chanting: "We are Scott Olsen."
The abiding images of the latest protests, though, will not be from the largely peaceful evening marches but from the clashes with police that erupted later at night.
Buildings had their windows smashed and makeshift barricades were set ablaze.
Police said protesters pelted them with concrete blocks, bottles and Molotov cocktails.
Officers in riot gear arrested a dozen people.
Several police were injured, although none needed hospital treatment.
The trigger for the clashes appeared to have been demonstrators' determination to occupy an empty office building in the city centre, which had been vacant since funding cuts forced the closure of a charity that had been based there.
A banner with the phrase "Occupy Everything" was slung over the door as people forced their way in.
The crowd passed around leaflets declaring the building had been taken for "reuse", while on Twitter the office was declared to be a new community centre.
The Port of Oakland said evening operations had been "effectively shut down", but it reopened yesterday morning after protesters removed a blockade limiting access.
Port spokesman Isaac Kos-Read said workers immediately began returning to their jobs and operations partially resumed.
In other cities, smaller-scale demonstrations were also held to show solidarity with Occupy Oakland and to protest the injuries to Mr Olsen.
New York, Philadelphia and Los Angeles saw small events.
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