VENEZUELA AND COLOMBIA
Length: 1,275 miles
Why it's so dangerous: Hundreds of leftist rebels leaving Venezuela and re-entering Colombia.
Background: A year ago, diplomatic relations were severed after then Colombian President Álvaro Uribe brought a complaint against Venezuela before the Organization of American States. Uribe accused Venezuelan President Hugo Chávez of supporting the Revolutionary Armed Forces of Colombia (FARC) and the National Liberation Army (ELN) in their 47-year campaign to overthrow the Colombian state.
Today: Relations could not be more different from a year ago. One of the first acts of Colombian President Juan Manuel Santos, who took office in August 2010, was to make up with Chávez. This improvement in ties has resulted in big changes on the ground for left-wing rebels -- long hidden on the Venezuelan side, beyond the reach of the Colombian security forces -- who are increasingly being confronted by Venezuela. As a result, approximately 200 guerrilla fighters have crossed the border back into Colombia, leading to a rise in violence along Colombia's Arauca border region. The border is now considered one of the most dangerous areas in Colombia, as the FARC have blown up oil and gas pipelines and attacked railways and Colombian security forces.
In March, the Colombian army intercepted a truck with rebel supplies from Venezuela. According to the military, the vehicle was carrying 1.5 tons of explosives, 16,000 feet of detonation cord, 17 rifles, 42,000 bullets, and almost 200 uniforms, all bound for the estimated 500 FARC rebels in Arauca. Despite the rise in violence, Colombian officials and residents along the border have welcomed the fact that Venezuela is taking action against the rebels. "There is still much to do, but our relations with the Venezuelan police are improving and there is real cooperation," Col. William Guevara, the chief of police in Arauca, said last week.
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