Bogota: Colombian authorities sought over the weekend to discredit a Swiss academic and former intermediary in talks with a left-wing rebel group who has been linked to a disputed report that officials paid $20 million (Dh73.4 million) for last week's release of 15 high-profile hostages.

A Colombian government official who asked to remain unnamed said Sunday that authorities suspect Geneva-based Jean Pierre Gontard was the source for the Swiss radio report last week stating that officials paid ransom for the release of the hostages.

Officials have denied any ransom was paid and said the rescue was based on subterfuge and infiltration of the rebel high command.

The notion of paying ransom is extremely sensitive here, as US and Colombian authorities have labelled the Revolutionary Armed Forces of Colombia (Farc) a terrorist group and have ruled out payments to terrorists.

Money courier

Meanwhile, Colombian Defense Minister Juan Manuel Santos told the newspaper El Tiempo that captured rebel computer files name Gontard as the courier for $480,000 (Dh1.76 million) seized by Costa Rican police at the behest of the Columbian government earlier this year.

Gontard, reached at his home early yesterday in Geneva, declined to comment on the $480,000 allegation, but strenuously denied leaking information to Swiss public radio station Radio Suisse Romande. "It absolutely was not me who spoke to the radio programme," Gontard said.