Trelew massacre The Trelew Massacre was the retaliatory government killing of 16 militants of different Peronist and left organizations held as political prisoners in Rawson Penitentiary . The prisoners were recaptured after an escape attempt and subsequently shot down by marines led by Lieutenant Commander Luis Emilio Sosa in a simulated new attempt to escape . The marines forced the prisoners to fake a new escape , then executed them as revenge by the dictatorship for the successful escape of some of their comrades during the initial prison break . The massacre took place on the morning of 22 August 1972 in the Almirante Marcos A . Zar Airport , an airbase of the Argentine Navy near the city of Trelew , Chubut in Patagonia . Evasion . On 15 August at 18 : 30 , 110 captured guerrillas attempted a massive escape from the prison at Rawson , the capital of Chubut Province in Argentina . In their escape the guerrillas shot dead one guard ( Gregorio Valenzuela ) and another ( Justino Galarraga ) was critically wounded . Only six of the 110 inmates ( members of the People ' s Revolutionary Army ( ERP ) , Revolutionary Armed Forces ( FAR ) and Montoneros ) succeeded . According to Galarraga ( who survived by feigning death ) , Valenzuela was shot in the head as he lay wounded by the pregnant wife of Santucho . The planner and head of the operation was Mario Roberto Santucho , leader of the Revolutionary Workers Party , although some reports say that Marcos Osatinsky ( FAR ) had started to plan the prison escape even before the arrival of Santucho . These two leaders along with Fernando Vaca Narvaja , Roberto Quieto , Enrique Gorriarán Merlo and Domingo Menna made up the so - called " Leakage Committee " , and were the only ones able to escape , thanks to a waiting Ford Falcon , and get to Trelew airport where a BAC One - Eleven airliner Southern Company , previously captured by a guerrilla group of supporters whose members were passengers , waited to take the escapees to the neighboring country of Chile , then ruled by socialist President Salvador Allende . Other vehicles , which should have been waiting for the rest of the escapees , weren ' t at the front of the prison due to a misunderstanding with the previously agreed - upon signals . However , a second group of 19 escapees managed to reach the airport on their own via three taxis , but arrived just as the aircraft took off . Recapture . When they saw their chance of escape disappear , this group called a press conference , laid down their arms without resistance and surrendered to the military personnel of the Navy that surrounded the area , hoping to get a government guarantee for their lives in the presence of journalists and judicial authorities . A military patrol under the command of Lieutenant Commander Luis Emilio Sosa , deputy chief of the Naval Air Base Almirante Zar , led the recaptured prisoners via a public transport unit to that military facility . Rejecting the prisoners ' request to return to Rawson Prison , Captain Sosa argued that the new site would be temporary but necessary as a prison riot at Rawson was still going on . Unfortunately , the judge Alejandro Godoy , the director of the newspaper " Jornada " , the deputy director of the newspaper " El Chubut " , " LU17 " director Hector " Pepe " Castro and the lawyer Mario Abel Amaya , all of whom accompanied the prisoners as guarantors for their safety , were not allowed to enter with them under the excuse that the number of people was too large , and were forced to leave . The spectacular escape attempt and partial success of the six top guerrilla leaders , who later managed to travel from Chile to Cuba , had the military government of the self - proclaimed Argentine Revolution and the public in suspense for tense days . The general feeling was that bloody reprisals would occur if the six escaped rebel leaders were not returned to Argentina . Because of this perception , on the morning of August 17 Justicialist Party sent a telegram to Interior Minister Arturo Mor Roig ( part of the Radical Party board ) stating that they demanded respect for human rights of the political prisoners in the Rawson prison unit , and that they held him responsible for all the prisoners ' safety and well - being . Shooting . While the government of Alejandro Agustin Lanusse tried pushing the president of Chile Salvador Allende into deporting the political escapees as criminals , the whole area of Rawson and Trelew were virtually occupied by military forces of the army and gendarmerie , who were patrolling continuously and made additional escape attempts impossible . The air base in Trelew maintained a large force of three thousand troops from the Navy . In such a high tension climate , members of the Board of Chiefs of the three armed forces , employees and ministers met the night of August 21 at the Government House . They didn ' t provide any information to waiting news reporters . That same night , at 03 : 30 hours on August 22 , at the Almirante Zar Naval Base , the 19 detainees were suddenly awakened and led out of their cells . According to the testimony of the three surviving prisoners , they were forced to look at the floor and gunned down by a patrol under Lieutenant Commander Luis Emilio Sosa , and the lieutenan t Roberto Bravo . Most died on the spot , while the injured were each given a coup d ' grace . The official version of events indicated that there was a new escape attempt , with 16 dead and three wounded among the prisoners , but no casualties in the ranks of the Navy . That night , the government sanctioned Law 19 . 797 , which banned any dissemination of information regarding guerrilla organizations . In the following days , there were demonstrations in major cities of Argentina , and a number of bombs were placed in government offices to protest the killings . Those killed were : Survivors : Revenge for the killings . Two of the main people responsible for the massacre , Vice - Admiral Hermes Quijada and minister Arturo Mor Roig , were later killed by the ERP . On the first anniversary of the Trelew massacre , 150 demonstrators were arrested and four policemen injured , apparently by gasoline bombs . On the second anniversary of the massacre , ERP guerrillas attacked a police station in Virreyes and seriously wounded a policeman . That same day a dozen bombs were set off in Cordoba and La Plata . On the eve of the third anniversary , left - wing gunmen in the city of Cordoba attacked the central police headquarters with automatic fire and bombed the police radio communications centre on 21 August , killing five policemen and wounding four . On 22 August 1975 , Montoneros guerrillas set off an underwater demolition charge in the engine room of the Argentinian destroyer Santisima Trinidad , causing extensive damage but no casualties . On the fourth anniversary of the killings , two busloads of left - wing guerrillas attacked a highway police station in Buenos Aires suburb of Florencia Varela and 10 bombs exploded at street corners and subway stations , injuring three people . The Argentine Secretary for Human Rights , Eduardo Luis Duhalde , who represented some of the 19 political prisoners , said about the massacre : References . Argentimes . com