BOGOTA, Colombia (AP) -- Clashes between leftist guerrillas and right-wing paramilitary groups have paralyzed a southern Colombian state and sent residents fleeing toward the Ecuador border, local officials said Monday.
The army said troops were trying to control the violence between the armed groups battling over control of coca plant production in southern Putumayo state, which was largely cut off by road from the rest of the country.
``Businesses have begun to close their doors, food supplies are running out and it is impossible to get gasoline,'' Putumayo state Gov. Jorge Devia told reporters in Colombia's capital, Bogota.
There were unconfirmed reports of high casualties on both sides in the clashes that began Sept. 21. Putumayo's food supplies were also drying up as rebels of the leftist Revolutionary Armed Forces of Colombia, or FARC, threatened to destroy vehicles that venture onto the highways.
``People are heading for Ecuador,'' Roger Hernandez, town secretary of the small coca-growing town of La Hormiga, told The Associated Press by telephone.
Putumayo, which borders both Ecuador and Peru, is Colombia's largest producer of coca plants, the raw material for cocaine, with an estimated 140,000 acres cultivated.
``The battle for coca territory is fundamental here,'' Col. Gabriel Diaz, the commander of the army's 24th Brigade based in Putumayo, said in a telephone interview.
Hernandez did not have an estimate of how many people were heading for the border, and U.N. refugee officials in Bogota were not immediately available for comment. In Ecuador, Red Cross workers and the military said they have not confirmed the presence of Colombian refugees, although they had heard rumors that some crossed the border.
Colombia's neighbors have expressed growing concern about refugees and a spillover of violence as the country gears up for a U.S.-backed anti-drug offensive targeting Putumayo and neighboring Caqueta state. The planned entry of some 3,000 U.S.-trained troops into the volatile area is expected to intensify violence between the FARC, which is the country's largest leftist rebel group, and the rightist United Self-Defense Forces of Colombia.
In other violence Monday, a car bomb exploded next to a savings bank in the northeast oil-refining city of Barrancabermeja, killing two women and injuring seven other people. Police did not immediately cast blame, but guerrillas and paramilitary groups are active in the port on the Magdalena River.
Separately, Colombia's second-largest guerrilla group kidnapped 10 employees from a toll booth in northwest Antioquia state on Monday, the government reported. Hours later, the National Liberation Army released six of the hostages, all women.