Thanks in part to dramatically improved security in recent years, Colombia has vaulted into the major leagues of global crude producers…[T]hat same success may be driving a surge in violent crime against oil workers flooding into areas formerly considered off-limits to outsiders. About 130 companies are now looking for oil in the Colombian countryside…But risk remains a harsh reality in Colombia, as seen recently in a spate of attacks, kidnappings and killings mostly attributed to leftist rebel groups. Although the government and industry analysts say the attacks have not yet caused oil companies to suspend operations or flee the country, industry sources warn that continued deterioration of hard-won security gains could jeopardize Colombia's oil boom...At least 38 oil field workers have been kidnapped so far this year across the country…[Ecopetrol, Occidental Petroleum, Emerald Energy, Geoenergy]