Protesters confront government troops, Bangkok, Thailand, April 10, 2010. In a clash between Red Shirt protesters and the Thai military, hundreds of people are wounded and many killed as troops open fire on civilians. Several soldiers and two journalist are killed. A riot is a form of civil disorder characterized often by what is thought of as disorganized groups lashing out in a sudden and intense rash of violence against authority, property or people. While individuals may attempt to lead or control a riot, riots are thought to be typically chaotic and exhibit herd behavior, and usually generated by civil unrest. However, there is a growing body of evidence to suggest that riots are not irrational, herd-like behavior, but follow inverted social norms.