Panamanian Airborne Border Police patrol the Colombian border of the Darien Gap, a wilderness region straddling North and South America.

Colombia's nominally right-wing paramilitaries and left-wing guerrillas, known as the Revolutionary Armed Forces of Colombia (FARC), clash frequently in this region. Helicopter crews have been ordered to intercept armed fighters and to keep watch for drug traffickers, who use the jungle as cover.

Indigenous groups and environmentalists oppose a Colombian proposal to build a highway through the Darien, saying the road would hurt biodiversity and increase violence between guerrillas and paramilitaries.

Read the related story.