Intelligence obtained by U.S. forces based in Ecuador helped Colombia's military locate the senior rebel commander killed in a cross-border raid by Colombian troops last year, a government commission said Thursday.
The U.S. Embassy denied any such help was provided.
The 131-page report by the special investigative commission also confirmed there are links between Colombian rebels and parts of Ecuador's government, which Colombian leaders have long charged.
The report said Ecuador's then-security minister met with the rebel chief, Raul Reyes, at his camp in Ecuadorean territory three weeks before the attack of March 1, 2008.
The minister, Gustavo Larrea, has denied he met inside Ecuador with Reyes, the No. 2 leader and foreign minister of the Revolutionary Armed Forces of Colombia, or FARC.
Larrea has claimed that meetings discussed in documents found stored in laptops recovered by Colombian commandos at the destroyed camp were held in a third country that he has refused to identify.
The Colombian raid, which claimed 25 lives, created an international uproar, with the leftist presidents of Venezuela and Ecuador dispatching thousands of troops to the border. Ecuador has still not restored full diplomatic relations.
A third key finding of the commission is that the FARC rebels have penetrated Ecuador's police, judiciary and other sectors of the neighboring nation's society.
That finding comes as little surprise to Colombia's government. In July, it leaked to The Associated Press a video showing a FARC commander disclosing that the rebels made contributions to the 2006 campaign of President Rafael Correa.
Correa has denied any knowledge of such contributions.
The commission's report said Correa had no prior knowledge of Reyes' camp inside Ecuador.
Its lead author, Francisco Huerta, told reporters that the commission also found no evidence of ties between Correa's government and the FARC.
It did, however, determine that an official in Larrea's office, Jose Ignacio Chauvin, met with Reyes seven times.
The report, whose authors refused to take questions from reporters as they released it, offers no specifics on the electronic intelligence that it says the U.S. obtained through its operations at the Manta air base on Ecuador's Pacific coast.
The report said only that "strategic intelligence processed from the Manta base was fundamental to the pursuit and location of Raul Reyes as a priority target for Colombia's government."
The U.S. ambassador in Quito, Heather Hodges, denied to the report's authors that the U.S. planes based at Manta "had the capacity to realize such a mission," the report said.
On Thursday, U.S. Embassy spokeswoman Martha Youth said the U.S. had repeatedly "rejected categorically those allegations." She said U.S. forces at Manta engaged only in the interception of drug traffickers in the eastern Pacific.
Senior Colombian officials, who spoke on condition of anonymity, previously told the AP that U.S. planes provided electronic intelligence that assisted Colombian forces in the raid. The Colombian bombers also had U.S. avionics.
U.S. troops, who had conducted counternarcotics flights from Manta since 1999, left in September after Correa refused to renew a 10-year lease.
Associated Press Writer Frank Bajak in Bogota contributed to this report.