WASHINGTON (AP) -- The U.S. State Department invited Cuban
                  President Fidel Castro on Thursday to substantiate his claim that
                  Miami-based Cuban exiles have been planning to assassinate Venezuelan
                  President Hugo Chavez.

                  "We would be happy to see any detailed information on criminal behavior by
                  U.S. citizens that Castro would provide us, and we would forward it to
                  appropriate law enforcement agencies for analysis," spokesman James P.
                  Rubin said.

                  Castro said Tuesday in an interview with Venezuelan journalists that the
                  killing was to be committed in December by a commando group with money
                  provided by a member of the Cuban-American National Foundation.

                  Castro gave a street address in Miami where he said the plot was based.
                  The address turned out to be the office for a tiny, 2-year-old group,
                  "Plantados until Freedom and Democracy in Cuba."

                  In Miami Wednesday, Eusebio Penalver, head of the five-member group,
                  denied Castro's accusations that they were planning to assassinate Chavez.

                  "He's a big liar," said Penalver, who was jailed in a Cuban prison for 28
                  years. "He's bothered by the work that this little group has done all over the
                  world." A "plantado" is a person who firmly plants his feet -- in this case
                  while struggling for freedom and democracy in Cuba -- Penalver said.

                  All the group's members spent more than 20 years in Cuban jails.

                  "Our mission is to help those in Cuba fight with dignity for freedom against
                  social injustice," said member Ernesto Diaz Rodriguez, 60. He was jailed for
                  22 years and wrote a book about his imprisonment.

                  Castro said his intelligence services discovered the plot to kill Chavez whose
                  critics maintain wants to imitate the Cuban revolution.

                  Rubin noted that Castro did not provide evidence to back up his charge. He
                  added that Castro "has a history of making unfounded accusations against
                  the United States."