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By Ayman al-Warfalli

BENGHAZI, Libya, May 30 (Reuters) - A force that controls key oil terminals in eastern Libya said it had captured the town of Ben Jawad from Islamic State, pushing the militant group back along a coastal strip they control east of their stronghold of Sirte.

Spokesman Ali al-Hassi said four Petroleum Facilities Guard (PFG) fighters had been killed and 16 wounded in fierce clashes in the coastal town, and that fighting was continuing in the nearby town of Nawfiliyah.

The PFG claim, if it was independently verified, would prove significant as it might signal the start of a new front in the campaign against Islamic State.

The PFG has declared its support for Libya's U.N.-backed unity government. Other brigades that back the government advanced last week to the outskirts of Sirte from the west.

"We launched today's attack to purge and liberate the central region from Daesh (Islamic State), and secure this area under the umbrella of the ministry of defence and the Presidential Council, the Supreme Commander of the Libyan army," Hassi said. The Presidential Council is the unity government's leadership.

Western states hope the unity government, which arrived in Tripoli at the end of March, can resolve Libya's political crisis and bring together armed factions to fight Islamic State.

Islamic State took advantage of a security vacuum in Libya to seize control of Sirte last year, extending its presence along about 250 km (155 miles) of coastline either side of the city.

In January the group announced it had established full control over Ben Jawad, about 150 km east of Sirte. It also attacked the oil terminals of Es Sider and Ras Lanuf, situated a little further east, clashing with the PFG and causing extensive damage.

Libya's unity government is designed to replace two rival administrations that competed for power from Tripoli and eastern Libya, both backed by loose alliances of armed brigades.



(Reporting by Ayman al-Warfalli; Writing by Aidan Lewis; Editing by Richard Balmforth) ((Aidan.Lewis@thomsonreuters.com ; +216-29850352;))