Unknown attackers blew up a section of an oil pipeline in northeast Colombia near the Venezuelan border, the company Petronorte said Wednesday.
"We cannot say who did this but we know it was an attack, an explosion" at the Rio Zulia-Ayacucho pipeline, Petronorte spokesman Renzo Coronado told RCN Radio.
The spokesman did not indicate how much oil was spilled but said efforts were underway to control the damage and prevent contamination of the Catatumbo river.
The area has seen several attacks in recent days by the Revolutionary Armed Forces of Colombia (FARC), a Marxist group fighting the government for decades.
The government contends the rebels in the region are involved in the smuggling of drugs and fuel and other crimes.
The Colombian government earlier this month rebuffed a call from the new leader of the FARC to revive peace talks and told the militants to prove the move was genuine.