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VIllAVICENCIO - A Venezuelan mission to pick up three hostages held for years by Colombian rebels in jungle camps was delayed again on Saturday because guerrilla leaders have not given the final go-ahead.
After weeks of promising to release two former politicians and the young son born to one of them in captivity, the Revolutionary Armed Forces of Colombia, or FARC, has not yet revealed their location, Red Cross officials said.
Hugo Chavez, the leftist firebrand president of neighbouring Venezuela, has led the rescue effort and initially hoped to have the hostages freed on Thursday, but government sources said it would not now happen until Sunday at the earliest.
Chavez sent two helicopters into Colombia on Friday, but they remained grounded in the flat, hot and humid town of Villavicencio at the foot of the Andes mountains.
The Red Cross, which is helping co-ordinate the rescue, said it needed exact directions and daylight to set out to look for the captives.
"The key part is the co-ordinates and it is hard to say when we are going to get them," said Yves Heller, a spokesman for the International Committee of the Red Cross in Colombia, adding that the helicopters will not fly at night.
Foreign envoys sent to observe the rescue effort were set to fly to Villavicencio close to a rebel stronghold later on Saturday.
They include former Argentine President Nestor Kirchner and officials from France and Switzerland, and United States film director Oliver Stone was expected to join them.
Although wary of Chavez and his goal of uniting South America under socialism, Colombia's conservative government let him fly Venezuelan aircraft painted with the colours of the Red Cross deep into its territory to collect the hostages.
Chavez is also trying to get the location from the rebels and called for patience. He said poor communications from FARC jungle territory and bad weather were holding up the mission.
He had said earlier that Consuelo Gonzalez, Clara Rojas and her son Emmanuel could be free within hours of the arrival of the helicopters. Emmanuel, whose father is a guerrilla fighter, was born in a rebel camp and is thought to be four years old.
Rojas was captured in 2002 and Gonzalez in 2001.
Colombian President Alvaro Uribe told Chavez last month to stay out of negotiations with the rebels, but Chavez opened informal talks and struck a deal to free the three captives.
Guerrilla leaders say they will turn the hostages over only to Chavez or someone designated by him.
Villavicencio, in central Colombia, is a gateway to the country's southern jungles where the FARC controls wide areas used to produce the cocaine that funds its insurgency.
Roadblocks dotted the area on Saturday with police checking identity papers as the local airport swarmed with journalists waiting for the operation to begin.
The release could help pave the way for freeing other rebel-held captives, including French-Colombian politician Ingrid Betancourt and three American anti-drug contractors, in exchange for jailed guerrillas.
It would also give Chavez a political victory just weeks after he lost a referendum vote that would have allowed him to run for re-election indefinitely and given him sweeping powers to accelerate his socialist revolution in Venezuela.
Chavez will not take part in the rescue party, but he plans to receive the freed hostages at a Venezuelan air force base close to the border, where relatives of the long-time captives will also gather.
Stone, who is making a documentary about Latin America, toured the base with Chavez on Friday. He said he was a fan of the Venezuelan leader, calling him a "great man".
- REUTERS