Smoke is seen rising from the Brigade Qaqaa headquarters.

TRIPOLI — The Libyan parliament that was replaced in an election in June reconvened on Monday and chose an Islamist-backed deputy as the new prime minister, leaving the chaotic country with two rival leaders and assemblies, each backed by armed factions.

As political unrest mounted, U.S. officials said two series of air strikes in the past week on armed Islamist factions in the capital, Tripoli, were the work of Egypt and the United Arab Emirates. However, late on Tuesday the State Department issued a statement saying the comment on Libya was “intended to refer to countries reportedly involved, not speak for them.”

Egypt has denied conducting air strikes or other military operations in Libya.

At a meeting of Libya’s neighbors on Monday in Cairo, Libya appealed for international protection of its oilfields and airports, saying it lacked the power to stop armed groups.

An election in June had been aimed at rebuilding state institutions in an attempt to quell three years of spreading violence since the ouster of long-time ruler Muammar Gaddafi.

But the old General National Congress (GNC), where Islamists had a strong voice, has refused to acknowledge the legitimacy of its successor assembly, the House of Representatives, which is dominated by liberals and federalists.

The GNC reconvened after armed factions from the western city of Misrata forced a rival faction from Zintan out of Tripoli’s main airport on Saturday after a month of fighting that has come to symbolize the country’s deep divisions.

The Zintanis and Misratis joined forces in 2011 to topple Gaddafi, but have now turned their weapons on each other to achieve a power monopoly and exploit Libya’s oil resources.

The Misrata-led brigade, backed by an Islamist militia called Operation Dawn, had called on the GNC to resume work. Many in Misrata feel the new parliament does not represent the majority. The Zintan faction opposed the old assembly.

The GNC, which met in Tripoli, appointed Omar al-Hasi as prime minister.

“The House of Representatives is the only legitimate body in Libya,” Prime Minister Abdullah al-Thinni told a televised news conference, condemning as invalid the GNC decision to appoint a new prime minister.