[Video link, from "Stop the Machine," aka October 2011, the anti-war group that attempted to occupy the National Air and Space Museum today in Washington, DC. Shot by Nathan Schneider.]

Update: Sounds like a right-wing agent provocateur was in the mix, and may have been at least partly responsible for escalating the situation.

A group of protesters in the nation's capital tried to force their way into the National Air and Space Museum on Saturday. Security guards responded with force, pepper spraying some of the demonstrators. The museum closed two hours early.

An Air and Space staffer tweeted that it seemed not all of the demonstrators supported the idea of pushing into the museum, where an exhibit of unmanned aerial drones is one of 22 major exhibitions currently on display. But with large crowds full of agitated people, things happen.

And that is why we can't have nice things like this—well, for today, anyway.

Coverage: CNN, Washington Post.

Update: According to eyewitnesses I'm following on Twitter, and some Boing Boing commenters in this thread, and a later report from the Associated Press, the protesters who attempted to enter the museum and protest the military drone exhibit were not part of the Occupy DC group. A number of people were made sick by the attack with pepper spray, with vomiting and other symptoms reported. Being maced is an agonizing experience. From available reports, it sounds like guards at the museum, not police, were responsible for the decision to use pepper spray—and the situation sounds like it must have been volatile.

Snip from AP:

Smithsonian spokesman John Gibbons said a large group of demonstrators, estimated at 100 to 200 people, arrived at about 3 p.m. and tried to enter the National Mall museum. When a security guard stopped group members from entering, saying they could not bring in signs, he was apparently held by demonstrators, Gibbons said. A second guard who arrived used pepper spray on at least one person and the crowd dispersed, he added.

Museum staff tell Boing Boing that astronaut John Glenn, the first American to orbit the earth and the third American in space, was visiting the museum at the time of the incident. I am told he was escorted out when things got out of hand.

That's John Glenn. A living national treasure. Who is 90 years old. Nice going, guys.