Town of al-Ukeirshi witnessed in 2015 the mass execution of militants by IS after many had attempted to desert its ranks
US-backed Syrian militias have captured a town south of the city of Raqqa where the Islamic State (IS) group ran a major military base and training camp, a spokesman for the militias said on Tuesday.
An alliance of Kurdish and Arab militias fighting under the banner of the Syrian Democratic Forces (SDF) is trying to oust IS from its headquarters in Raqqa.
SDF media official Mustafa Bali said the militias had seized the town of al-Ukeirshi, some 15km south of Raqqa on the Euphrates river.
The SDF pushed into Raqqa last month after a long offensive, backed up by air strikes and special forces from the US-led coalition.
A series of recent advances along the southern bank of the Euphrates have allowed the SDF to completely besiege the militants inside Raqqa and to press on the south of the city.
The SDF alliance, led by the Kurdish YPG militia, has also been waging fierce battles inside the Old City of Raqqa since last week after US-led coalition jets breached its historic walls.
In al-Ukeirshi, IS killed scores of its own forces execution-style in 2015 for desertion or on accusations of treachery, said the Britain-based Syrian Observatory for Human Rights.
The militants who were executed had attempted to escape IS after fighting the group inside Syria. The majority of those killed were from Central Asia and of Chechen descent.
According to the SOHR, after the militants were executed, their bodies were taken to the Raqqa countryside and left in a "natural hole" which was turned into a body dump by IS after it took control of the area.
IS named the training camp it established in the town of al-Ukeirshi after Osama bin Laden, the founder of the al-Qaeda militant group killed by US forces in 2011.