Shortly after 6 pm, with red-and-black flags waving, several dozen protesters left Colonel Summers Park, as promised, for an anti-police-brutality march that had the Portland Police Bureau concerned enough that it sent out a pre-emptive arrest warning earlier in the afternoon.

The marchers were chanting in unison, “NO JUSTICE, NO PEACE, FUCK THE POLICE!” And, yes, they were mostly members of the anarchist Black Bloc crowd, dressed in the usual black and with bandanas over their faces.

Windows were smashed. Cars were tagged. And, also as promised, Portland cops—some in riot gear—were on hand and ready with the handcuffs. (And also with some taunts of their own.) The Oregonian reported some nine arrests in connection with the protest, an unpermitted march meant to show solidarity with the 400 Occupy protesters arrested in Oakland last month. (The Oregonian over-stated the number of protestors they counted 175, I counted no more than 80).

As we mentioned earlier, tonight's march wasn't technically an Occupy march—although many of the marchers are Occupy Portland participants. And that tension was on display as the Black Bloc helped escalate the protest into a mini riot.

The first incident was on SE Yamhill, when a car trying to avoid the marchers slowed to a near stop. Seeing an opportunity, masked protesters spray-painted the driver's rear window with an anarchy symbol.

“Why are we spray painting regular people’s cars!?” yelled a woman from the crowd.

Ten minutes later the group continued on its circuitous route from the poorly lit residential Yamhill to the brightly lit storefronts of Belmont. Near SE 28th, a masked protester used the metal staff holding his red-and-black flag to bust two holes in the window of Genoa Restaurant. Take that, 1 percent!

The next piece of property to feel the marchers' wrath was a blue BMW parked at SE 30th and Stark, just up from Stark Naked Pizza. A protester again used a flagstaff. He smashed the vehicle’s windshield and passenger-side window.

The mild destruction elicited cheers form some protesters and boos from others.

At SE 26th and Stark, the cops moved in. They even enjoyed a laugh at the expense of the marchers.

Talking through a loudspeaker from a white van, the police declared that SE Stark was being cleared and that “anyone one left in the street would be subject to arrest.” The officer talking into the loudspeaker could be heard holding back a laugh, and when the street was cleared actually said, “Take that, baby.”

The group headed back to Belmont, where some pulled a dumpster out into the street. At this point unmasked protesters started shoving their masked compatriots and pushed the dumpster back to the curb.

Next, the anarchists knocked over a recycling bin, and again unmasked protesters picked the contents and placed them back in the bin.

The protesters continued to SE Morrison, just next to the Lone Fir Cemetery. There, they learned the police were waiting for them at SE 20th. Trying not to get outflanked, the protesters found an open spot between buildings and headed back to Belmont. The police still managed to outflank them.

Then the 15 or so riot police, 10 or so cops on bikes, and the five horse-riding police officers all moved in and starting making arrests.

At 23rd and Belmont, an unmasked man was arrested.

“I was just crossing the street,” he screamed as he was handcuffed

Brent Georgeson, an unmasked protester, said he saw the police knock the man off his bike.

“I don’t think breaking car windows and store windows is the best way to get the message across,” said Georgeson. “I mean I don’t know if the street is a good place to have a discussion like that.”

He was holding a red-and-black flag, which he said he had picked up because he was concerned someone might use it to break something else.

As police in full riot gear stormed Belmont, several other protesters were handcuffed and hauled away in police cars.

"This is not Occupy doing this,” said Bao Vuong from Occupy Portland, trying to distance the movement from the Black Bloc. “This is a group of anarchists, and we have asked them not to do this and they don’t listen.”

After the arrests on Belmont, the protesters scattered. As of an hour or so ago, a small group had made their way to SE 36th and Hawthorne. Vuong, who followed the group, said he saw at least two more arrests.