Daniel "El Loco" Barrera, alleged to be Colombia's last major drug lord, has been caught in neighbouring Venezuela in an international sting operation, Juan Manuel Santos, the country's president, has said.
"The last of the great capos has fallen," Santos announced on national television and radio late on Tuesday, declaring that the US Central Intelligence Agency (CIA) and Britain's MI6 foreign intelligence service had provided support.
Barrera, whose outfit is estimated to have sent more than 900 tonnes of cocaine to the US and Europe, was caught in the Venezuelan city of San Cristobal, said Santos, who listed the drug lord as having criminal ties to FARC (Revolutionary Armed Forces of Colombia) rebels and paramilitaries.
"This is perhaps the most important capture of recent times," the president said, thanking the Venezuelan government for its help.
Tareck El Aissami, the Venezuelan interior minister, confirmed the arrest on Twitter, calling it a "major coup" for his country and adding that "images" and "details of the operation" would be released on Wednesday.
Venezuela's foreign ministry said Barrera was captured "after an intelligence operation carried out by Venezuelan authorities", without mentioning any foreign involvement.
Hugo Chavez, the Venezuelan president, has long had rocky relations with Washington and regularly accuses the US of trying to undermine his leftist government.
Santos said the operation "was led from Washington," adding that the head of Colombia's national police, General Jose Leon Riano, had helped direct it from the US capital.
Speaking from Washington, Leon Riano told the Caracol television network that authorities had tracked Barrera for four months before arresting him at a phone booth in San Cristobal.
He added that the operation had been orchestrated from Washington because it required "special technical support". US authorities could not immediately be reached for comment.
In 2010, the US Treasury had named Barrera a "special designated narcotics trafficker," saying he faced criminal charges in New York and was allied with the FARC.
In the 1980s and early 1990s, Colombian cartels dominated the American drug trade, but a US-supported government crackdown has left local gangs in increasing disarray.
In 2011, 252 of Bogota's 1,632 registered homicides - 15.4 per cent were linked to drugs - according to official figures.
The regional cocaine trade, however, is still alive: in 2011 Colombia was the world's largest cocaine producer, according to a UN report, although neighbouring Peru is expected to overtake it soon.
Colombian criminal gangs, as well as leftist guerrillas and right-wing paramilitary groups, sell the cocaine to Mexican criminal syndicates, who then smuggle it into the US and Europe.