TRIPOLI, April 17 (Xinhua) -- Libya's National Oil Corporation (NOC) declared a state of force majeure over the El Feel oil field on Sunday as protesters forced the closure of the country's major oil field.

       A group of protesters stormed the oil field and forced the workers to stop production, the NOC said in a statement.

       Operated by Italy's energy giant Eni and the NOC, the El Feel oil field produces about 70,000 barrels of crude oil per day (bpd), out of the nationwide 1.2 million bpd, according to government figures.

       Oil and gas represent a major source of Libya's revenue. However, the sector has suffered over the past years from armed conflict and closures of oil fields and ports.