 On December 1976 Buendía left his post in CONACYT to become a full @-@ time columnist . He then worked at El Sol de México , a newspaper owned by Organizacion Editorial Mexicana . After facing some differences with the owners of the print media company , Buendía left on 17 August 1978 to work at El Universal , a newspaper based in Mexico City . Only lasting until December of that year , he left to work at Excélsior , a daily newspaper with one of the largest circulations in Mexico City . At this newspaper , Buendía wrote for the column Red Privada , which was distributed and read in over 200 newspaper across Mexico . In his column he wrote about the covert operations of the CIA in Mexico during the Cold War , ultra @-@ rightwing groups , crooked businessmen , and corrupt government officials involved in drug trafficking . His investigations angered many in Mexico 's political elite and made him a frequent target of death threats . Buendía took the death threats he received very seriously and thereby carried a pistol , either on his belt or in a leather pocket . Prior to his death , Buendía wrote extensively on the alleged corruption within Mexico 's Petroleum Workers Union ; the allegations of wrongdoings of Jorge Díaz Serrano , former leader of Pemex , the national oil company ; and Arturo Durazo Moreno , the former head of Mexico City 's police force . Buendía also criticized the role of the U.S. government and the CIA in Mexico , and often published names of American officials involved in secret operations . Although he was quick to publish controversial reports , Buendía 's direct reporting was respected and generally considered reliable given his access to top Mexican officials . He was the most @-@ read journalist in Mexico 's print media , and is often cited by newspapers and journalists as the most influential political columnist in Mexico of the second half of the 20th century . 
