Forces aligned to Libya's UN-backed unity government Tuesday said they had captured one of three remaining Islamic State-held districts in the city of Sirte, the extremist group's last stronghold in the North African country.
Forces of the Bunyan Marsous Operation seized Sirte's Second District, Ahmed Ruaiti of the operation's media office told dpa.
The advances leave the militants surrounded in the city's central First and Third districts, with their only apparent escape route by sea.
Islamic State controlled a 250-kilometre stretch of Libya's central Mediterranean coast before forces aligned to the nascent Government of National Accord began operations against it in May.
The jihadist organization built up its presence in Libya in 2015, taking advantage of a conflict between rival governments based in Tripoli and in the east of the country.
Analysts said it had sent senior figures to Libya as its main territory in Syria and Iraq came under pressure from Kurdish and Iraqi government forces backed by an intensive US-led air campaign.
The nascent national unity government led by Prime Minister Fayez Serraj was intended to overcome the country's divide. However, the administration in eastern Libya, and its powerful military chief Khalifa Haftar, have so far refused to back Serraj.
In recent weeks, Haftar's forces have reportedly moved towards the central eastern oil port of Zueitina, raising fears of a military confrontation between militias aligned to the two governments.
Libya has suffered from military and political chaos since the overthrow of long-time dictator Moamer Gaddafi in a 2011 uprising.