SAN VICENTE DEL CAGUAN, Colombia (Reuters) -- Colombia's leading
                  Marxist rebels said Tuesday they had absolved a rebel leader accused of ordering
                  last year's brutal kidnappings and killings of three American activists.

                  Colombian and U.S. authorities have said German Briceno, a feared commander
                  of the Revolutionary Armed Forces of Colombia, was directly responsible for
                  ordering the abduction and subsequent killings of the Americans, which sparked
                  an international outrage.

                  But Raul Reyes, the FARC's chief spokesman and a member of its ruling general
                  secretariat, said an internal investigation had cleared Briceno, who is known by
                  the alias "Grannobles," of any responsibility in the case.

                  "The investigation shows that Grannobles had nothing to do with this," Reyes
                  told reporters in this town in southeast Colombia, which lies as the center of a
                  Switzerland-sized zone the government has demilitarized to promote peace talks
                  with the FARC.

                  "We can't punish him or put him before a war council (rebel court) because
                  there's nothing to hold against him," he added.

                  He said three other rebels, including a man the FARC has previously described as
                  a rogue field commander, were still being investigated for the killings, however.

                  The three are suspected of killing the Americans, who were working with U'wa
                  Indians in northeast Colombia, because they were believed to be U.S. drug or
                  intelligence agents, Reyes said. Colombia's chief prosecutor has already charged
                  Grannobles with ordering the murders of Terence Freitas, Ingrid Washinawatok
                  and Lahneenae Gay.

                  He has also ordered Briceno's brother Jorge, the FARC's chief military strategist,
                  to give evidence in the case, which opened in March 1999 when the blindfolded
                  bodies of the Americans were found dumped just across Colombia's border with
                  Venezuela.

                  Freitas, 24, of Oakland, California; Washinawatok, 41, of New York; and Gay,
                  39, of Hawaii; were helping the U'wa plan a strategy to prevent Occidental
                  Petroleum Corp. of the United States from encroaching on their tribal lands to
                  drill for oil, which the Indians see as "the life blood of Mother Earth."

                  Their deaths forced the U.S. State Department to break off tentative talks with
                  the FARC, which were being carried out in Costa Rica and aimed at supporting
                  the Colombian government's efforts to end an internal conflict that has taken
                  35,000 lives over the past decade.

                  The Briceno brothers both took a public role in Saturday's formal launch of the
                  FARC's new political party, a clandestine organization dubbed the Bolivarian
                  Movement for a New Colombia.

                  Both faced a long list of criminal charges including "terrorism" before the case of
                  the Americans broke and are unlikely to ever surrender to the authorities.