The group continued the violent campaign even after democratic elections and the return to civilian rule in 1973 , with Juan Peron 's return . On June 20 , 1973 the Peronist movement split after the Ezeiza massacre , that started when Lieutenant-Colonel Jorge Osinde 's crowd monitoring right-wing Peronist militia reported the arrival of heavily armed Montoneros in two buses the day that Peron returned from exile . Victor E. Samuelson , an Exxon executive , was abducted on 6 December 1973 by the ERP . He was released after 144 days in captivity , after the Exxon Corporation paid a record ransom of $ 14.2 million . The avowed aim of the ERP was a communist revolution against the Argentine government in pursuit of " proletarian rule . " The ERP publicly remained in the forefront . ERP guerrilla activity took the form of attacks on military outposts , police stations and convoys . In 1971 , 57 policemen were killed fighting the left-wing guerrillas , and in 1972 another 38 policemen lost their lives in the guerrilla violence . On 28 December 1972 , Marine Private Julio César Provenzano of the ERP , is killed when the bomb he planted in one of the lavatories of the Argentine Naval Headquarters went off prematurely . On 3 April 1973 , ERP guerrillas kidnapped Rear-Admiral Francisco Agustín Alemán
Ezeiza massacre
Ezeiza massacre
People's Revolutionary Army (Argentina)