Kurdish-led troops have made a key incursion against Islamic State in the group's Syrian stronghold of Raqqa, breaking into the old city after breaching the first line of the militants' defence and scaling an ancient perimeter wall.
News agency Deutsche Welle, citing US sources, claims the Kurdish-led Syrian Democratic Forces broke through the Isis defenders guarding the wall in the old city.
Kurdish military spokesman Nuri Mahmud told agency Efe via telephone that his troops can now be found in the outskirts of the old city, after scaling the walls that ring it. The troops were divided into three groups advancing from the east, with aerial support from the US-led coalition.
US sources claim their bombardment focused on two small sections of the ancient wall, clearing these stretches of traps and snipers and allowing the SDF troops to burst through. It also claims the majority of the historic structure remains intact.
The Syrian Observatory for Human Rights claims fighting has been ongoing since daybreak, after 16 Isis militants died in skirmishes on the southern outskirts of the city last night. It is not clear how many SDF fighters have died in the last few hours.
Raqqa, which became Isis' biggest and most recognisable stronghold when the group burst to prominence in 2014, is now widely seen as its final remaining frontier, after the jihadists were driven from vast swathes of territory in Iraq and Syria. The group also suffered a major blow last month when it was reported that leader Abu Bakr al-Baghdadi had been killed in an airstrike.