Cienna reports that protesters have dispersed downtown after trying to get arrested for the past two hours—blocking access to the US Customs office and blocking streets—to raise awareness about immigration reform. Police reportedly told organizers of the group of 40 people engaging in civil disobedience (surrounded by a couple hundred surrporters) that they would not arrest anyone.
The order to not arrest has reportedly has come from the mayor's office. Organizers are declaring the event a victory, citing recent support from the city council (to boycott Arizona, which recently passed a draconian anti-immigration law) and now from Mayor Mike McGinn. That said, organizers are threatening to protest again.
I have calls in to the mayor's office and the SPD to confirm.
UPDATE: Mayor's office spokesman Arron Pickus says, "No, the mayor did not call to prevent arrests."