Late on a moonless night in March, a plane smuggling nearly half a ton of cocaine touched down at a remote airstrip in Honduras. A heavily armed ground crew was waiting for it - as were Honduran security forces. After a 20-minute firefight, a Honduran officer had been wounded and two drug traffickers lay dead.

Several news outlets briefly reported the episode, mentioning that a Honduran official said the U.S. Drug Enforcement Administration had provided support. But none of the reports included a striking detail: That support consisted of an elite detachment of military-trained DEA special agents who joined in the shootout, according to a person familiar with the episode.

The DEA now has five special commando-style squads that it has been quietly deploying for the past several years to Western Hemisphere nations - including Haiti, Honduras, the Dominican Republic, Guatemala and Belize - that are battling violent, transnational drug cartels, according to documents and interviews of law enforcement officials.

The program - called FAST, for Foreign-deployed Advisory Support Team - was created during the George W. Bush administration to investigate Taliban-linked drug traffickers in Afghanistan. Beginning in 2008 and continuing under President Barack Obama, it has expanded far beyond the war zone.

"You have got to have special skills and equipment to be able to operate effectively and safely in environments like this," said Michael Braun, a former head of operations for the drug agency who helped design the program. "The DEA is working shoulder-to-shoulder in harm's way with host-nation counterparts." (...)