Unidentified war planes attacked targets in Libya's capital Tripoli on Sunday hours after forces from the city of Misrata said they had seized the main airport.
Tripoli residents heard jets followed by explosions at dawn but no more details were immediately available.
Forces from the Libyan city of Misrata on Saturday seized Tripoli's main airport after more than a month of fighting with a rival group, a Misrata spokesman said.
Pictures on social media purportedly showed Misrata fighters celebrating at the terminal building and standing on civilian planes in what, if confirmed, would be a big development in the battle to control the capital.
Arab channels Jazeera and Al-Arabiya also said Misrata forces were controlling the airport, although Reuters was unable immediately to access the area. Heavy shelling could be heard in other parts of the city.
War planes had earlier struck Misrata positions in Tripoli in an attack claimed by renegade general Khalifa Haftar. The raids killed 10 people and wounded dozens, the Misrata faction said.
The fighting is the worst since the overthrow of Muammar Gaddafi in 2011.
In the NATO-backed campaign to oust Gaddafi, fighters from the western region of Zintan and Misrata, east of Tripoli, were comrades-in-arms. But they later fell out and this year have turned parts of Tripoli into a battlefield.
Haftar launched a campaign against Islamists in the eastern city of Benghazi in May and threw his weight behind the Zintan fighters.
In Saturday's fighting, residents heard explosions early in the morning near the airport, where the two groups have been fighting for control for more than a month.
Local television channel al-Nabaa said planes had attacked four Misrata positions. A Misrata spokesman said the planes had come from Egypt and the United Arab Emirates, two countries which have cracked down on Islamists.
But Haftar's air defense commander, Sager al-Jouroushi, told Reuters that his forces were responsible for the attack. Haftar's forces also claimed responsibility for air raids on Misrata positions in Tripoli on Monday.
POSITIONS:
Egypt's president denied any military involvement in neighboring Libya, a day after Islamist militias accused Cairo of bombing their posts in Tripoli.
Egypt's state news agency MENA carried President Abdel-Fattah el-Sissi's comments on Sunday. They came in response to accusations a day earlier by Islamist militias in Tripoli, who blamed Egypt and the United Arab Emirates for a series of mysterious airstrikes. The Libyan air force denied it was behind the attacks last week. Two airstrikes killed 15 fighters and wounded another 30 on Saturday.
El-Sissi said his armed forces have not carried out any military operations outside Egypt "so far."
He said Egypt is in consultation with Libya's neighbors to find a political solution to the violent power struggle between rival groups.
REUTERS/AP