Alirio de Jesus Pedraza Becerra was last seen on 4 July 1990 in Bogota. Eye-witnesses report that he was seized by about eight armed men; some reports claim that Dr. Pedraza’s abductors identified themselves to two police agents who were present. Official inquiries have been initiated into his “disappearance” but his whereabouts remain unknown. Dr Pedraza was a member of the Comite de Solidaridad con los Presos Politicos (CSPP) and has worked on behalf of peasants and trade unionists. Since his “disappearance”, a number of human rights workers have received anonymous death threats, namely Sandra Munoz, Elvia Uran and Martha Luz Saldarriaga Velez. A colleague of his, Dr Daniel Libreros Caicedo was detained in March 1990 but released a few days later.