An attack in the city of Raqqa has killed six members of the Kurdish-led Syrian Democratic Forces (SDF), officials said.
SDF commander Mazloum Abdi said in a statement on Monday that an ISIL (ISIS) cell had targeted security and military buildings in the city, killing six fighters and wounding an unspecified number of others.
He added that intelligence gathered by the group “indicates serious preparations by [ISIL] cells”.
Siamand Ali, a spokesman for the Kurdish-led Syrian Democratic Forces, told The Associated Press that a group of five people believed to be part of an ISIL sleeper cell, two of them wearing explosive belts, had attacked checkpoints and guard points of Raqqa’s Internal Security Forces.
During the ensuing clashes, he said, one of the attackers was killed and another arrested. SDF and Internal Security Forces units are searching for the remaining attackers, he said.
The Syrian Observatory for Human Rights, a Britain-based opposition war monitor, reported that the attack targeted an area containing the headquarters of the SDF’s Internal Security Forces, anti-terrorism units, and a military intelligence prison where about 200 ISIL prisoners are held.
The observatory noted that the attack was the 16th operation carried out by suspected ISIL sleeper cells in SDF-controlled areas since the beginning of this month.
Also on Monday, the observatory and the National Front for Liberation, a coalition of Turkish-backed rebel groups, reported that six members of the coalition were killed in clashes with the SDF and the Syrian army in the Aleppo countryside.
Abdi, the SDF commander, cast blame for the ISIL attack in Raqqa partially on Turkey, which has carried out a campaign of airstrikes against the SDF in northeast Syria since late November and has threatened a ground invasion.
“[The] terrorist activity coincides with the continuous Turkish threats to target the security and stability of the region,” said Abdi.
Ankara blames Kurdish groups in Syria for a deadly November 13 explosion in Istanbul, an allegation the groups deny.
SDF units briefly halted joint anti-ISIL patrols with United States-led coalition forces due to the Turkish strikes but resumed them earlier this month.
Last week, US Central Command said American forces had arrested six ISIL fighters in three raids in eastern Syria. The SDF said separately that its fighters had also detained an ISIL fighter who managed cells in eastern Syria.