Oil spill at Shell deepwater field off Nigeria

Shell confirmed it had shut production at its Bonga deepwater facility off the coast of Nigeria Wednesday, after a leak sent oil spilling into the sea.

"Early indications show that less than 40,000 barrels of oil have leaked in total," Shell Nigeria said in a statement.

The company said the leak occurred Tuesday during a routine operation to load oil into a tanker. An export line between the storage vessel and the tanker was the "likely source" of the problem, according to Shell's statement, and has since been shut off to halt the flow of oil.

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Production at the 200,000-barrels-per-day oil field has been shut down temporarily as a "precautionary measure," Shell said, without indicating when production would resume.

Bonga, located some 75 miles off Nigeria's coast, produces around 10 percent of the country's crude, according to Bloomberg. The field was Shell's first deepwater discovery in Nigeria, Africa's largest oil producer and a big supplier to the US.

Shell Nigeria chairman Mutiu Sunmonu said the company was "sorry" for the leak and planned to focus on "a speedy and effective clean-up."

Nigeria's Petroleum Resources department and the National Oil Spill Detection and Response Agency have been notified.

Shell plans to open an investigation into the incident, a spokesperson told Reuters.

The company has faced criticism for its operations in Nigeria before. Amnesty International accuses Shell of failing to clean up two major oil spills in the Niger Delta in 2008, causing damage that the UN Environment Program estimates it will take $1 billion and more than 25 years to repair.

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