Libya said it halted the Sharara field, its biggest oil producer, following a rocket attack at the connected Zawiya refinery, threatening almost 30 percent of the OPEC member’s production.

The Sharara field, producing about 250,000 barrels a day before the disruption, was shut as a precaution after an attack two days ago on the refinery, Mansur Abdallah, director of oil movement at the Zawiya plant, said by phone today. The North African nation, still restoring output after more than a year of political unrest and protests, was producing 870,000 barrels a day as of Sept. 14, National Oil Corp. spokesman Mohamed Elharari said that day.

The disruption “serves as a reminder that despite recovering export rates and the National Oil Corp.’s reassurances of stable supplies, the country remains in a state of civil war, where anything can happen,” Andrey Kryuchenkov, an analyst at VTB Capital in London, said by e-mail. […]