Oil giant Royal Dutch Shell says an oil spill this week in Nigeria's oil-rich Niger Delta was caused by sabotage, and that such attacks are on the rise.
In a statement Sunday, the oil company said their Cawthorne Channel-Bonny pipeline had been attacked three times in August.
said that in the three attacks, thieves drilled holes in the pipeline or cut it with hacksaws to siphon oil.
Shell said that following the latest incident, it cut oil to the pipeline to prevent leakage and was working to fix the damage and clean up the spill.
The company did not give details on the extent of the spill or the impact the sabotage incidents has had on Shell's Nigerian output.
In Sunday's statement, Shell claimed 98 percent of oil spilled in 2009 was the result of sabotage, but said it had cleaned all spills, regardless of the cause.
Shell said the damage from the two earlier attacks in August had already been repaired.
Saboteurs in Nigeria sometimes cut oil lines to steal crude oil to sell to illegal refineries.
Shell's oil facilities in Nigeria also have been the regular target of militants, who have blown up pipelines, kidnapped oil company workers and fought government troops since 2006. The militants call for Niger Delta residents to get more of the region's oil wealth.
Some information for this report was provided by AP and Reuters.