BENGHAZI, Libya — Heavily armed Libyan militias clashed in Tripoli on Monday, killing at least 20 people and forcing the capital’s only airport to close, officials said.

The Health Ministry said another 63 people were wounded in the fighting between two militias that are ostensibly allied with the internationally backed government, underscoring the lingering instability in the country seven years after a popular uprising toppled long-ruling dictator Moammar Khadafy.

Civilians were among the dead, including an airline employee who was trying to get home after Matiga airport shut down.

An airport official said that staffers were evacuated from Matiga airport, and that five flights have been canceled. A picture posted on the airport’s Facebook page showed a passenger plane with its roof blown off.

The Special Deterrent Force, a militia that controls the airport, was fighting a rival militia led by local strongman Bashir al-Baqara. Both are allied with the internationally recognized government in Tripoli.

ASSOCIATED PRESS