The incident, which took place early Tuesday, caused serious damages to the building and tore down the wall surrounding the embassy.
Two vehicles parked near the embassy were also destroyed.
The Libyan government is struggling to control its borders and making efforts to retrieve the arms and explosives that were looted after longtime dictator Muammar Gaddafi was deposed in August 2011.
The central government has little authority beyond the capital, and the country is fractured by militias, tribes, and regional loyalties.
The chaos in Libya since the fall of Gaddafi’s government has implications far beyond the border areas.
Arms and explosives stockpiled by the Gaddafi government are being smuggled to Mali and Egypt’s Sinai Peninsula and to the foreign-backed militants fighting the Syrian government.