It is alleged that Escobar backed the 1985 storming of the Colombian Supreme Court by left-wing guerrillas from the 19th of April Movement, also known as M-19. The siege, a retaliation motivated by the Supreme Court studying the constitutionality of Colombia's extradition treaty with the U.S., resulted in the murders of half the judges on the court. M-19 were paid to break into the Palace and burn all papers and files on "Los Extraditables", a group of cocaine smugglers who were under threat of being extradited to the U.S. by the Colombian government. Escobar was listed as a part of "Los Extraditables". Hostages were also taken for negotiation of their release, thus helping to prevent the extradition of "Los Extraditables" to the U.S. for their crimes.