SDF detains 63 suspected IS militants in Syria raid

The US-backed Syrian Democratic Forces said those detained belonged to "terrorist cells directly responsible for spreading terror and chaos" in the city.

At least 48 suspected members of the Islamic State group were among those arrested, according to Rami Abdel Rahman, the head of the Britain-based Syrian Observatory for Human Rights.

He said that members of rival opposition groups are also among those detained by Kurdish security forces in Raqqa, once the de facto capital of IS's self-proclaimed "caliphate".

The arrests are part of a sweeping crackdown on alleged IS sleeper cells in territory controlled by the SDF, the Observatory said.

IS is clinging to a tiny sliver of its once sprawling "caliphate" and many residents are fleeing and turning themselves in ahead of a final offensive. 

A spokesman for the Kurdish-led Syrian Democratic Forces, Mustafa Bali, said IS fighters were hiding among the fleeing civilians. 

"On a daily basis, we are arresting foreign IS fighters," he told AFP, 

The SDF has captured at least 50 foreign IS fighters over the past three weeks, Kurdish foreign affairs official Abdel Karim Omar told AFP on Wednesday, days after confirming the capture of German jihadist Martin Lemke. 

More than 37,000 people, mostly women and children from jihadist families, have fled IS territory since the SDF, backed by the US-led coalition, intensified its offensive against the jihadists in December, according to the Syrian Observatory for Human Rights. 

The Britain-based war monitor has said that figure includes some 3,200 jihadists. 

Kurdish authorities say they have in their custody hundreds of foreign male IS members.

They allegedly include several German IS members, such as Mohammad Haydar Zammar, a Syrian-born German national accused of helping plan the September 11 attacks, and 36-year-old jihadist Sufyan, who travelled to Syria in 2015 to join the group.  

Suspected jihadists captured by the SDF are usually eager to be sent home. 

The Kurdish administration in northeastern Syria also wants to send the prisoners back for trial, but governments in their countries of origin are often reluctant. 

The SDF has whittled down IS territory in Syria to a tiny sliver of land near the border with Iraq.

Jihadists have responded by ramping up bomb attacks and assassinations targeting SDF forces elsewhere.

The city of Raqqa, which was taken by the SDF in 2017 after a massive operation by the US-led coalition, has been hit by a spate of bombings in recent weeks.

On Monday, an explosion wounded Kurdish security forces in the city, the Observatory said. Last month, an IS suicide bomber attacked a centre for Kurdish forces, killing four civilians and a Kurdish fighter.

The Observatory says that suspected IS sleeper cells have allegedly assassinated at least 50 civilians and 135 SDF fighters in Kurdish-held territory, including eastern Deir az-Zour, Hasakeh's countryside, Raqqa and Manbij since August.

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