Three Colombia airmen killed in helicopter bombing

BOGOTA (Reuters) - Three Colombian airmen were killed when suspected FARC rebels detonated explosives just as their helicopter landed in a training exercise near one of the country's largest military bases, authorities said on Tuesday.

Attacks on Colombian military aircraft are rare since President Alvaro Uribe began using billions of dollars of U.S. aid to drive back the guerrillas and reduce violence from the country's four-decade-old insurgency.

The bombing came late on Monday as the airmen practiced landings in Tolima province, the site of Tolemaida military base, where U.S. advisors train the army. The area is a popular weekend tourist spot for Colombians escaping from the capital.

"Explosives were placed 100 meters from the area where it was going to land, leading to the helicopter's total destruction and the death of the three crewmen," Colombian Air Force commander Gen. Jorge Ballesteros said.

"Without any doubt, it has all the characteristics and methods of the FARC," he said.

Officials, who originally said the aircraft had crashed, said investigators found detonation cord near the landing site and suspected that rebels rigged the bomb knowing the area was used for training.

Violence from Colombia's long conflict has eased as Uribe has sent troops to retake areas once controlled by illegal armed groups. Bombings and attacks on urban areas are scarce though rebels are still fighting in remote areas.

Last year, Colombian authorities said they had foiled a plot by rebels to attack U.S. military advisors as they visited Melgar, a popular resort near the Tolemaida base. Three men were arrested with explosives and photographs of the area.

Since 2000, Colombia has received around $5.5 billion in mostly military assistance from Washington to fight leftist guerrillas and cocaine traffickers -- the largest U.S. aid package outside the Middle East.

(Reporting by Patrick Markey and Luis Jaime Acosta in Bogota, editing by Jackie Frank)