Colombia's largest rebel group is calling on the actor Denzel Washington and the film-makers Oliver Stone and Michael Moore to help it reach a deal with the US government on exchanging imprisoned guerrillas for rebel-held hostages, including three US citizens

"US citizens" or "mercenary spies"?

The three American hostages - Thomas Howes, Keith Stansell and Marc Gonsalves - were military contractors on an intelligence-collecting mission when their aircraft went down in 2003 in southern Colombia and they were quickly captured.