updated 6:51 p.m. ET July 3, 2008

WASHINGTON - The U.S. military said it flew thousands of spy flights over Colombian jungles trying to find and free three Pentagon contractors since their kidnapping in 2003.

In the end, U.S. officials said, it was a daring operation by Colombian military intelligence agents that finally rescued the American trio from leftist rebels.

Until this week's rescue, some U.S. government officials despaired that Tom Howes, Marc Gonsalves and Keith Stansell might ever be freed. Some counterterror, military and diplomatic officials familiar with Bush administration efforts to secure their release questioned whether enough was being done.

On Thursday, Col. William Costello, spokesman for the U.S. Southern Command, said the command made 3,600 intelligence, surveillance and reconnaissance flights, followed up on 175 intelligence leads and spent $250 million trying.

"We've been actively searching for these guys every day for the past five and half years," Costello said.

FBI spokesman Richard Kolko said the agency sent crisis negotiators and investigators on "countless trips to Bogota" since the kidnapping.

'A supporting role'
One official said a Defense Intelligence Agency cell that primarily works to track captured or missing U.S. troops has been working on the case of the civilian contractors, who had been held by the Revolutionary Armed Forces of Colombia since their drug-surveillance plane went down in the jungle in February 2003.

Another said it was U.S. intelligence that located the hostages.

A third said the U.S. Special Operations Command helped with surveillance that positively located the hostages within the past year using satellites, aircraft and ground reconnaissance — and had tracked them since then.

All three spoke on condition of anonymity because they were not authorized to speak on the record and the Bush administration was adamant about giving the Colombians the credit.

"This was a Colombian-planned and Colombian-executed operation," State Department spokesman Sean McCormack told reporters. "We were in a supporting role."

Officials have said the U.S. and Colombian governments have known the location of the hostages a number of times over the years — and planned rescue missions several times. But they didn't attempt them because of the difficulty of the jungle terrain and the risk that the hostages could be killed.

Tricking guerillas
Finally, it was a trick by Colombian spies that persuaded the rebels to hand over the men, along with kidnapped presidential candidate Ingrid Betancourt and 11 others on Wednesday.

Colombian Defense Minister Juan Manuel Santos said military intelligence agents infiltrated the guerrilla ranks and led the local commander in charge of the hostages to believe they were being taken to the guerrillas' supreme leader.

The reluctance of U.S. officials to highlight the U.S. role may be a reflection of American politics.

Congressional support for Plan Colombia — the multibillion-dollar U.S. aid package to Colombia to help it fight its war on drugs and the insurgency — has rested heavily on promises that no U.S. troops would be put at risk and drawn into a jungle war with rebels, said George Withers, senior fellow with the Washington Office on Latin America, a human rights advocacy organization.

Congress has capped the number of American troops and contractors to explicitly limit the extent of U.S. involvement there to under 1,500 people, which indicates Congress' wariness of U.S. military involvement in action there, Withers said.

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