U.S. Marines on a jungle-patrol exercise in Guatemala Cpl. Daniel Negrete/U.S. Marine Corps A team of 200 U.S. Marines have begun patrolling Guatemala's western coast in an unprecedented operation to combat drug trafficking in Central America, the AP reports.

Operation Martillo (i.e. Hammer) will target fast power boats and self-propelled "narco-submarines," primarily those of the Zeta cartel, along Central America's Pacific coast with the help of four UH-1 "Huey" helicopters.

The U.S.-led operation involves troops or law enforcement agents from Belize, Britain, Canada, Colombia, Costa Rica, El Salvador, France, Guatemala, Honduras, the Netherlands, Nicaragua, Panama and Spain.

"This is the first Marine deployment that directly supports countering transnational crime in this area, and it's certainly the largest footprint we've had in that area in quite some time," Marine Staff Sgt. Earnest Barnes of U.S. Southern Command told AP.

The last time the U.S. sent any significant aid and equipment into Guatemala was in the '50s and '60s when the CIA and the Green Berets provided funding, training and weaponry to support counter-insurgency efforts against a "communist threat".

That effort led to 36 years of war that left 200,000 dead, mostly indigenous Maya farmers, and numerous human rights violations before the U.S. pulled out in 1978.

Guatemalan President Otto Perez Molina said in February that he would propose legalizing drugs in Central America—saying that the U.S.-backed the war on drugs had not diminished drug trafficking in the area— but on July 16 his government signed a treaty allowing the U.S. military to conduct the operations.

"We fight a highly mobile, disciplined and well-funded adversary that threatens democratic governments, terrorizes populations, impedes economic development and creates regional instability," U.S. Rear Adm. Charles Michel told AP, noting that authorities are able to stop only one out of every four suspected traffickers they spot.