Demonstrators, one holding a poster of opposition presidential candidate Henrique Capriles, confront riot police from behind a burning barricade in the Altamira neighborhood in Caracas, Venezuela, Monday, April 15, 2013. National Guard troops fired tear gas and plastic bullets to disperse demonstrators protesting the official results in Venezuela's disputed presidential election.(AP Photo/Ramon Espinosa)

Associated Press
Demonstrators, one holding a poster of opposition presidential candidate Henrique Capriles, confront riot police from behind a burning barricade in the Altamira neighborhood in Caracas, Venezuela, Monday, April 15, 2013. National Guard troops fired tear gas and plastic bullets to disperse demonstrators protesting the official results in Venezuela's disputed presidential election.(AP Photo/Ramon Espinosa)
Demonstrators, one holding a poster of opposition presidential candidate Henrique Capriles, confront riot police from behind a burning barricade in the Altamira neighborhood in Caracas, Venezuela, Monday, April 15, 2013. National Guard troops fired tear gas and plastic bullets to disperse demonstrators protesting the official results in Venezuela's disputed presidential election.(AP Photo/Ramon Espinosa)