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"Tumbada en la manga y oculta entre helechos, una mujer trigueña, vestida de uniforme camuflado, brazalete del rojo y negro con las insignias del ELN (Ejército de Liberación Nacional), apuntaba con un fusil a su enemigo imaginario."

This is weird. At first, I was thinking manga referred to sleeves, so I thought maybe she was lying on her stomach propped up on her elbows (which were inside her sleeves... a stretch, I know...). And then, I thought maybe they were referring to a grove of mango trees, which is possible. But I can't tell if she's leaning against a tree or lying on a branch of the tree (unlikely, because she is hidden by ferns) or if the ferns are covering the floor of the mango grove. One of the other Kudoz questions mentions a cattle chute at a dairy farm, and it's possible that this could be in a dairy farming area, but I can't imagine a cattle chute would be covered in ferns. Any other ideas? Thanks.