REVENGE ATTACK

The Corinthia, a luxury high-rise overlooking the capital's coastline, is frequently used by top government and foreign delegations. In 2013, the then-Libyan prime minister was briefly abducted from the hotel by former rebels on the state payroll.

On Tuesday, Khadrawi, the capital's security director, said security forces had spirited the Tripoli government's premier, Omar al-Hassi, from the 22nd floor of the hotel, where he was staying, to safety. Four Americans were also rescued, he said.

"The attackers were attempting to assassinate him," he said.

But SITE monitors, citing social media, said a militant group had claimed the attack as revenge for the death of Abu Anas al-Liby, a suspected al Qaeda member accused of helping plan the 1998 bombings of the US embassies in Tanzania and Kenya. Liby died in a New York hospital this month ahead of his trial.

The Libyan national was snatched by US Special Forces from Tripoli in 2013.

Since the 2011 NATO-backed uprising that toppled Gaddafi, Libya has struggled to find stability and a conflict has gradually emerged between two loose confederations of politicians, armed groups and regional factions.

Tripoli is controlled by a faction that is allied to the city of Misrata and their powerful armed forces, but also includes some Islamist-leaning former rebel fighters and politicians allied to the Muslim Brotherhood.

They are faced by the internationally recognised government of Prime Minister Abdullah al-Thinni and the elected parliament who now operate out of the east of Libya. Thinni's government is allied to several armed factions, including a former Gaddafi army general battling Islamist militants in Benghazi.