U.S. energy firm Chevron said on Monday it had suspended production from an oil pipeline in Nigeria's Delta state, which was breached on Friday. Chevron said it was investigating the damage to the Dibi-Abiteye pipeline, which feeds the Escravos oil stream, but did not comment on how much production would be lost.

Escravos crude exports were due to be around 123,000 barrels per day in December, according to loading programmes. It was not clear how much this would be reduced by the pipeline damage.

We have suspended production to minimize environmental impact and have informed relevant government agencies and other stakeholders, Chevron said in a statement.

The breach is being investigated and we are reviewing our operations.

The Niger Delta Liberation Force (NDLF), a militant faction in Nigeria's oil-producing wetlands region, said on Saturday it was behind the attacks on oil facilities operated by Chevron and Italian oil company Eni .

The sabotage attacks followed raids earlier this month by a military task force comprising the army, navy and air force on camps believed to belong to John Togo, the suspected leader of the NDLF.

MILITANTS

President Goodluck Jonathan brokered an amnesty with militants last August, leading to more than a year without major unrest but there has been a resurgence in violence in the last two months.

Despite a series of recent successful operations by the military task force, it remains difficult to guard against pipeline sabotage attacks.

Onshore oil infrastructure in the Niger Delta, a network of shallow creeks opening into the Gulf of Guinea, is extremely exposed, with thousands of kilometers (miles) of pipeline passing through remote and thickly forested terrain.

Africa's largest energy industry has been held back for years by strikes on pipelines and infrastructure by military groups who say they are fighting for a more even distribution of the oil wealth.

But the line between militancy and crime is blurred with some gang leaders growing rich on the spoils of kidnapping for ransom and the theft of industrial quantities of oil.

Previous militant campaigns have knocked out a significant chunk of the OPEC-member's oil output, currently averaging around 2.2 million barrels per day (bpd), and cost it as much as $1 billion a month in lost revenues.

(Additional reporting by Alex Lawler in London; editing by William Hardy)

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