A man was bundled out of the public gallery above the Commons chamber by security during prime minister's questions on Wednesday, after throwing marbles at the glass screen that protects MPs.
The disturbance happened while David Cameron was mocking Labour's shadow business secretary Chuka Umunna for pronouncing Worcester as Wichita. The marbles made a loud bang on the screen. Most MPs taking part in PMQs appeared not to notice. But the disturbance was clearly visible to journalists sat in the press gallery directly opposite the public seating area.
According to reports, the man was shouting "I'm English, you're all idiots" before he was tackled by security. Parliamentary ushers also suggested he had smuggled the marbles into parliament in his underwear.
Members of the public are able to watch MPs . A thick glass screen was erected between the public gallery and the Commons chamber below after Tony Blair was hit with condoms full of purple flour in 2004.
Today's incident will be an embarrassment for parliament's security operation. It infamously failed in 2011 when a man managed to launch a foam pie at Rupert Murdoh as the media mogul gave evidence to a Commons committee on phone hacking.