Arrests as US protests disrupt West Coast ports

At least one port was fully closed down, while freight traffic was disrupted at several others including in Oakland, where thousands of demonstrators rallied after a day of action from California to Alaska.

There were also 11 arrests at a port in Seattle, Washington state, local media reported.

Seventy-five percent of longshoresmen - 150 out of 200 - in Oakland were sent home due to companies shutting docks due to safety concerns in the area, said a International Longshore and Warehouse Union spokesman.

The Port of Oakland said in an end-of-day update that there had been disruptions and delays at "several" of the port's seven terminals during the day, and a few chose to close early to avoid further disruption.

Further north all operations were shut down at Portland, Oregon, authorities there said as darkness fell.

The Seattle Times, citing local police, said 11 protesters were arrested at the port's Terminal 18. Port authorities, however, said there had been "minimal impact" to cargo movement throughout the day.

In Long Beach, south of Los Angeles, two people were arrested after protesters marched on the port terminal of SSA Marine, a company 51 percent owned by Goldman Sachs, a key target of the Occupy Wall Street movement.

But by the afternoon the Port of Long Beach said there had been "minimal impact to port operations" during the rain-soaked demonstration by several hundred protesters at one of the world's largest shipping ports.

The protests were most high-profile in Oakland, where authorities wrote an open letter to protesters urging them not to shut down a port which handles around $39 billion in imports and exports each year.

Protest organizers in Oakland called on demonstrators to stay out until at least 3:00 am, when the next shift of workers were due to arrive. By late evening, however, the number of protesters had fallen to less than 100, although some of those said others would return and join them at 3:00 am.

The loosely organized, left-leaning Occupy Wall Street protesters insist they are exercising their freedom of speech in the run-up to November 2012 national elections.