Original sentence: Among the few intellectual co-authors of the extermination campaign  which have been identified with a relatively clear degree of certainty are druglords (such as Gonzalo Rodriguez Gacha) and paramilitary leaders (such as Carlos Castaño Gil, by his own admission).Like the main UP party, the UJP was severely persecuted by the agents of druglords, paramilitaries and rogue elements inside the Colombian military during the 1980s.Many left-wing groups in Colombia have denounced the extermination of the UP and the UJP as part of a politically motivated strategy emanating from  powerful sectors of Colombian society, including druglords and some members of the traditional socioeconomic elites, which would have counted with the passive or active collaboration of several officers within the Colombian military and allegedly the indifference or tacit approval from contemporary administrations, in particular that of Virgilio Barco Vargas.No proven direct links between the murders of UP members and high-ranking Colombian officials have been uncovered, though there is some documented evidence of the existence of organized meetings concerning the subject of the UP between druglords, paramilitaries and lower-to-medium ranking military individuals at the time.Several of the lower-ranking military officials which directly cooperated with  illegal death squads at the time were prosecuted for some of the killings, though the vast majority of the cases have remained unresolved
Edited sentence: Like the main UP party, the UJP was severely persecuted by the agents of druglords, paramilitaries and rogue elements inside the Colombian military.Many left-wing groups in Colombia have denounced the extermination of the UP as a government strategy but there have never been any proven links between murders of UP members and high-ranking Colombian officials, and many cases of lower officials cooperating with paramilitary groups and illegal death squads have been adequately brought to justice