The State Department ordered all non-emergency U.S. government officials to leave the country Sept. 12, one day after an attack on the U.S. consulate in Benghazi. That attack left U.S. Ambassador to Libya Chris Stevens and three of staff members dead.
The department said the U.S. Embassy in Libya is "an unaccompanied post" because of security concerns in Libya.
"The security situation in Libya remains unpredictable," a State Department advisory read. "Sporadic episodes of civil unrest have occurred throughout the country."
Libya is struggling to secure gains made since the end of civil war in 2011. U.N. special envoy to Libya Tarek Mitri called on all parties to use peaceful means to settle differences.
He was responding to attacks last week on the convoy of President of the General National Congress Mohammed Magariaf.
The Libya Red Crescent and international Red Cross added their concerns after several days of tribal clashes left more than 3,000 people displaced in the Nafusa Mountains, about 100 miles south of Tripoli.