Libya's National Oil Corporation (NOC) has shut down crude production at the Sharara oil field after a kidnapping.
The company said four employees were seized by unknown armed assailants on Saturday at station 186.
Two were later released, but the others remain captive.
The facility is run by Akakus, a joint between NOC, Total, Repsol, Statoil and OMV.
"Oil wells in the surrounding area have been shut down as a precaution, and all other workers evacuated," NOC said.
