May Day demonstrators in downtown Seattle erupted in chaos on Tuesday as black clad protestors used sticks to smash downtown store windows and ran through the streets disrupting traffic.

The traditional international day honoring labor drew hundreds of demonstrators for immigration rights and from the Occupy movement.

Mike McGinn, Seattle Mayor, signed an emergency order authorizing police to confiscate sticks, tire irons, hammers and other implements that might be used for continued destruction.

The order was targeted at protesters who carried flags and protest signs on long, heavy poles during marches that began shortly after noon. Police say the protesters then converted the poles to implements of urban destruction, attacking targets from Starbucks to NikeTown.

Authorities said the problems in Seattle began after a group of about 300 apparently peaceful protesters marched from Seattle Central Community College, formerly the scene of the long-running Occupy Seattle camp, toward the heart of downtown at Westlake Park.

From there, a group of about 75 protesters adopting the “black bloc” style of black clothing and masks began attacking banks, stores and a few upscale cars. “By 12:35, we had reports from officers of paint and rocks flying hammers and tire irons being used to damage property,” McGinn said.

“The 1st Amendment use of 5-foot-long, 3-inch-wide sticks is outweighed by our desire to preserve public safety,” McGinn said at a hastily called news conference.

Intense protests also broke out in Portland, where police reported at least a dozen arrests during long-planned May Day marches.

But arrests were difficult because many of the black bloc protesters then changed their clothing and blended back into the crowd, authorities and witnesses said.

John Diaz, Police Chief, said he had received worrisome reports before Tuesday’s events that anarchist groups were planning to disrupt the city’s traditional May Day marches.

“This is a city that loves protests, that’s proud of their ability to have protests, and the vast majority of the time, we’re able to do it quite well,” Diaz told reporters. “It’s extremely unfortunate that we have small groups of people wanting to hijack these events,” he said.

“There have been a couple of arrests, and I guarantee there will be more before the end of the evening.”

Police said the courthouse used by judges of the U.S. 9th Circuit Court of Appeals was among the buildings damaged, along with branches of Wells Fargo, Bank of America, HSBC and Homestreet banks.

In Portland, nonviolent protesters marched through the city and through a major downtown shopping mall, banging drums and chanting, “Whose streets? Our streets!”

Police said protesters left the city’s Waterfront Park at about noon and almost immediately began walking into traffic, where they were confronted by police who made several arrests.

At least two banks reported vandalism, including damage to an ATM and broken glass doors, with additional damage reports still flowing in, the Portland Police Bureau said in a statement.(msn)