Kurdish fighters are now in control of most of a stronghold of the so-called 'Islamic State' group ('IS') in northern Syria following a push under the cover of air strikes by the US-led coalition.
The UK-based Syrian Observatory for Human Rights said Syria Democratic Forces (SDF) have seized most of the town of Manbij amid fighting in northern neighbourhoods and the town's centre.
Mustafa Bali, a Syria-based Kurdish activist, said IS still holds some areas in Manbij, including the major north-western area of Sarab.
Mr Bali said "it's a matter of time" before SDF fighters capture the town.
If Manbij is captured by the SDF, it will be the biggest strategic defeat for 'IS' in Syria since July 2015, when the extremists lost the border town of Tal Abyad.