Anti-government "red shirt" protesters sleep at the Democracy monument, the site of fierce street battles with Thai security forces, in central Bangkok April 14, 2010. Thailand's opposition called off a march on an army base on Wednesday as the government vowed to hunt down "terrorists" it blames for the Southeast Asian country's worst violence in 18 years. Saturday's clashes, which killed 21 people and wounded hundreds, were not only Thailand's worst riots in 18 years, but may also have taken the country closer to the worst-case scenario in its five-year-old crisis: a fissure in the military along social and political fault lines dividing the country. [Agencies]