The United Nations Security Council has called an emergency meeting on Libya, after a renegade army commander ordered his forces to advance on the capital Tripoli. The advance by the Benghazi-based Libyan National Army threatens to topple Libya’s U.N.-backed government. The rebel force is reportedly better armed and controls a town just 60 miles from the capital. U.N. Secretary-General António Guterres appealed Thursday for a ceasefire.

Secretary-General António Guterres: “I want to make a very strong appeal, an appeal for all military movements to stop, an appeal for containment, calm, de-escalation, both military and political and verbal de-escalation.”

Libya has been plagued by factional fighting since a U.S.-led NATO intervention in 2011 toppled longtime authoritarian leader Muammar Gaddafi.