US presidential candidate, Jill Stein, arrested at debate.

Just choose whichever website you want (or just search "Jill Stein arrested") and read.

tl;dr: Jill Stein tried to get into debate. Police tried to stop her. Jill Stein tried to start a sit-in. Police arrested her for disrupting traffic. Shackled to chair for eight hours in polic custody.