Colombian authorities on Tuesday announced reinforced security around the city of Cali, host of the COP16 UN biodiversity summit, after guerrillas at war with the government targeted soldiers with a bomb overnight and shot dead civilians traveling in a car.

During this month's U.N. Biodiversity Summit, known as COP16, in the Colombian city of Cali, nearly 200 countries will be debating how they can save nature from the current rapid rate of destruction.

A surge in the cultivation of coca leaf, a precursor to cocaine, is fueling a wave of violence across Latin America.