Operation Anorí (1973–74), and then reconstituted their forces, with partial assistance from the Colombian Government of President Alfonso López Michelsen (1974–78), who allowed the ELN to break from and escape encirclement by the Colombian National Army. President López Michelsen helped the ELN in the hope of initiating peace negotiations with them in order to end the civil war. After this, the National Liberation Army of Colombia resumed financing its military operations by means of kidnap for ransom and the extortion of money from Colombian and foreign petroleum companies and by taxation of the private Illegal drug trade of Colombia. The ELN did not participate in the peace negotiations conducted between the Colombian government of President Andrés Pastrana Arango (1998–2002) and the FARC, yet did participate in an exploratory conference about possibly participating in peace negotiations. A Colombian government initiative towards granting the ELN a demilitarized zone in the southern region of the Bolívar Department was thwarted by right-wing political pressure from the United Self-Defense Forces of Colombia (AUC) whose paramilitary mercenaries conduct anti-guerrilla operations in that part of the Bolívar Department. First peace discussions: 2002–2017 Early contacts Previous contacts continued during the early days of the Álvaro Uribe Vélez government but eventually were severed, neither party being fully trusting of the other. Only in mid-2004 the ELN and the government began to make a series of moves that, with the announced mediation of the Vicente Fox government of Mexico, lead to another round of exploratory talks. On July 24, 2004 the ELN apparently abducted Misael Vacca Ramírez, the Roman Catholic Bishop of Yopal, though their reasons were not clarified. The kidnappers said that Ramírez would be released with a message, but "Francisco Galán", a senior jailed ELN commander who has often acted as an intermediary between the government and the ELN's high command, said he did not know whether the group was responsible. The Bishop was subsequently released by ELN members, in good health, on July 27, after his kidnapping had been condemned by Amnesty International and Pope John Paul II, among others. As far as is publicly known, he did not have any message to announce on behalf of the ELN. Eventually, the ELN questioned Mexico's participation in the talks, arguing that it did not have confidence in the actions of a government which voted against Fidel Castro's Cuba during a United Nations vote. This led the Mexican government