Number of tea party rallies that devolved into riots . . . zero.

(CNN) — A May Day protest in downtown Seattle turned violent Wednesday night, with police saying they resorted to pepper spray to disperse demonstrators who pelted them with whatever was at hand.

Seattle Police said the crowd tossed rocks, bottles, metal pipes, fireworks — and even a skateboard.

The clashes left eight officers with injuries, and police said they arrested 17 people, on various offenses including property destruction and assault.

The injured officers suffered mostly mostly bumps and bruises with the exception. One officer, however, was struck in the knee by a fist-sized rock, Seattle Police said.

During the clashes, police deployed flash-bang grenades and tackled unruly protesters to the ground.

Other demonstrators ran through the fog created by tear gas wearing masks and holding protests signs.

A woman who was driving by the protest scene was wounded, slashed by glass, when a protester hurled a glass bottle at her car, shattering her window, police said. She was treated by a medic at the scene.

Update: 

Seattle Police Department was live tweeting throughout the day and evening, with a mix of information and earlier on, when it was more peaceful, a bit of humor.

Best tweet of May Day? This one:

And in case, you thought that that was just humor, well, now no it wasn’t, there was actually a scuffle between anarchist clowns and superheroes trying to protect the citizenry and property of Seattle.

Police stepped in to help out the superheroes

But it didn’t stay calm.

King 5 has good coverage including an assault on a police officer around 3:15 on the video here.

Laughing At Liberals captured the anarchists attacking a news crew and trying to steal their camera, resulting in an arrest.

The crowd then surrounded a police van trying to take the arrested person away, and the police had to deploy pepper spray and “blast balls” (sound like fireworks and send out pepper).

What was the purpose of all this?

Laughing With Liberals found out:

HT: Invanalyst