Mr Henderson spent his 32nd birthday as a hostage

Mark Henderson, of Pateley Bridge, North Yorkshire, was among eight backpackers kidnapped on September 12 in the Sierra Nevada mountains by the National Liberation Army, or ELN.

On Monday, the ELN freed Asier Huegun of Spain and Reinhilt Weigel of Germany.

Mark's father Christopher Henderson said their release was "one more step" towards securing the freedom of his TV producer son Mark, originally from Lincoln.

Rebels "trusted"

"We are delighted to hear they have released the Spaniard and the German.

"We hope that Mark and the four Israelis are released as soon as possible."

The rebels said the other five, Mr Henderson and four Israelis, would be released before Christmas.

Roman Catholic church leader Rev Dario Echeverri, who witnessed the handover, said he trusted the ELN to honour their pledge to free the others.

The Colombian Government, helped by Roman Catholic Church mediators, has been trying to negotiate the release of the hostages for weeks.

Last month the ELN - Colombia's second-largest rebel group - released a video of the hostages, threatening to kill them if a rescue was attempted.

Another Briton, Matthew Scott, was abducted with the others on 12 September, but escaped soon after the kidnapping.

The hostage-takers are demanding an investigation into what they call the oppression of indigenous people by right-wing paramilitaries in the area.

On Saturday, officials from the Roman Catholic Church and human rights groups arrived in the Sierra Nevada mountains to look into the rebels' allegations.

The remaining five hostages are believed to be held in separate locations to help prevent them being rescued.

Despite the negotiations by church mediators, Colombian security forces are still intent on rescuing the remaining hostages and killing their captors.