juan roa sierra (november 4, 1921 – april 9, 1948) was a colombian known for assassinating colombian liberal leader and presidential candidate jorge eliécer gaitán on april 9, 1948. after he shot gaitán three times, mortally wounding him, a mob chased roa sierra down and killed him. the assassination of gaitan triggered "el bogotazo", riots that partially destroyed bogota and led to "la violencia", a period of violence that lasted until approximately 1958.