Islamic State militants clashed with a force guarding Libya’s Es Sider oil port, and fighting continued near the major export terminal, witnesses and troops said according to Reuters. No official was available to confirm the attack or details of how close the fighting was to the port.

Es Sider is protected by Ibrahim al-Jathran’s Petrol Facilities Guard, a federalist armed faction.  Islamic State tried to attack Es Sider once before in October last year, setting of a car bomb and raiding a perimeter gate. Last June, the group claimed to have finally succeeded in taking former President Muammar Qaddafi’s hometown, after overrunning a nearby power station in Sirte.

Es Sider and nearby Ras Lanuf oil ports have been closed for more than a year after fighting between rival factions for control of the state. Islamic State has gained ground in the turmoil since Gaddafi’s fall in 2011, but it has so far not managed to control any oil installations.