Police arrest 10 people at an "Occupy Portland" protest on Monday night.
About 100 protesters were marching against what they called acts of police brutality.
The demonstration shut down streets, blocked traffic and caused minor property damage in Oregon's biggest city.
Police said that shortly after the march began there was a stand-off between protesters and riot police.
Police then cleared the streets and the crowd began to disperse.
During this time small skirmishes broke out among various factions within the "Occupy" group.
Travis Brecher, Reuters
