Libyan Army Forces belonging to Libya’s rival government, that are part of the Alshorooq (Libya Dawn) operation to free oil ports, are seen on the outskirts of Al Sidra oil port Dec. 14, 2014.

ISIS militants clashed with a Libyan force guarding oil ports near Brega terminal on Saturday, killing one guard and wounding four including Ibrahim Jathran, leader of the Petroleum Facilities Guard (PFG), security and medical sources said.

ISIS has a base in the Libyan city of Sirte and has launched frequent attacks against oil facilities and ports, including major export terminals that are closed but controlled by Jathran’s PFG brigades.

The PFG is one semi-official armed group that is backing a new unity government in Libya, where two rival administrations and their loose alliances of former rebels have been battling for control after the 2011 fall of Muammar Gaddafi.

Fighting between PFG and a convoy of ISIS militants broke out 52 kilometres south of the Brega oil terminal early on Saturday, a PFG source and a medical source said.

“The four wounded included the commander of PFG, Ibrahim Jathran,” the PFG source said.

The new UN-backed unity government is trying to establish its authority over Libya, where a self-declared Tripoli government and a rival in the east and various armed factions have been vying for power and a share of the country’s oil wealth for two years.

ISIS’s rise in Libya worries Western governments who are offering military and financial aid to the new unity government. But the new administration is still establishing itself in Tripoli and faces resistance from hardliners who reject its authority.

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