BEIRUT - The US-backed Syria Democratic Forces alliance has crossed into Deir al-Zor province for the first time, as part of a US-backed offensive against Islamic State, a Kurdish military source said on Tuesday.
The advance is part of an operation to encircle and ultimately capture the ultra-hardline group's de facto Syrian capital of Raqqa in the north of the country.
The SDF, which consists of Kurdish and Arab fighters, had entered the northern part of Deir al-Zor province and captured a number of villages from Islamic State militants, the Kurdish military source told Reuters.
