Forces loyal to Libyan strongman Khalifa Haftar said Monday they had seized several districts of Derna, promising "imminent liberation" of the last jihadist bastion in the country's east.
Haftar's self-styled Libyan National Army launched an offensive on May 7 for the coastal city, home to about 150 000 people and held by hardline fighters since the uprising that ousted dictator Moamer Kadhafi.
"The LNA controls most of the city, but there are still pockets of resistance," its spokesperson General Ahmed al-Mesmari told AFP.
Mesmari said LNA forces were focusing on "sweep operations and tracking down terrorist elements".
The spokesperson called on displaced families to return to their homes in "liberated areas" of the city.
The Libyan Red Cross said Sunday it had delivered humanitarian aid to 6 000 people in western Derna's Bab Tobruk district, in addition to thousands of others who have fled fighting in the embattled city to nearby areas.
LNA forces have besieged the city for nearly two years, making it difficult for residents to access humanitarian aid.
Derna is held by a ragtag coalition of Islamist and jihadist militias, including groups close to Al-Qaeda, hostile to both Haftar and the Islamic State group.
He said the LNA would deploy across the city to take control of all areas and infrastructure.
The strongman, whose forces are backed by the United Arab Emirates and Egypt, warned his troops against taking "revenge" -- in particular against "terrorists" who surrender and give up their arms.
Libya has been wracked by chaos since the 2011 uprising that toppled and killed long-time dictator Kadhafi, with two rival authorities vying for control.
A UN-backed unity government based in Tripoli has struggled to assert its authority outside the west.