Obama's socialists are rioting with broken bottles, bricks, rocks and sticks.
In riots which continued through evening rush hour, about 300 protesters were reported to have remained from an initial crowd of 2,000 in Bloomfield, Pittsburgh’s Little Italy.
Frustrated in their attempts to reach the venue where world leaders are meeting the crowd, many of whom wore face-masks and armed themselves with rocks, broke windows at fast-food restaurants, a BMW dealership and a bank in the area, about a mile from the fenced-off convention centre
The march turned chaotic at just about the time that President Barack Obama and first lady Michelle Obama arrived for a meeting with leaders of the world's major economies.
The Obamas are bringing out the best in people.
The clashes began after hundreds of protesters, many advocating against capitalism, tried to march from an outlying neighborhood toward the convention center where the summit is being held.
The protesters banged on drums and chanted "Ain't no power like the power of the people, 'cause the power of the people don't stop."
The marchers included small groups of self-described anarchists, some wearing dark clothes and bandanas and carrying black flags. Others wore helmets and safety goggles.
One banner read, "No borders, no banks," another, "No hope in capitalism." A few minutes into the march, protesters unfurled a large banner reading "NO BAILOUT NO CAPITALISM" with an encircled "A," a recognized sign of anarchists.
Their worst nightmare came true.
There they are breaking down doors and busting windshields and the next thing you know the big bad police are asking them for identification.
"This is ridiculous. We have constitutional rights to free speech," he said.
The National Lawyer's Guild, a liberal legal-aid group, said one of its observers, a second year law student, was among those arrested. Its representatives were stationed among the protesters, wearing green hats.
"I think he was totally acting according to the law. I don't think he was provoking anyone at all," said Joel Kupferman, a member of the guild. "It's really upsetting because he's here to serve, to make sure everyone else can be protected. ... It's a sign that they are out of control."
The march had begun at a city park, where an activist from New York City, dressed in a white suit with a preacher's collar, started it off with a speech through a bullhorn.
"They are not operating on Earth time. ... They are accommodating the devil," he said. "To love democracy and to love the earth is to be a radical now."