US-backed fighters in Syria have captured a senior Daesh leader who served as an assistant to the group's self-declared "caliph" Abu Bakr al-Baghdadi, they said on Friday.
The Syrian Democratic Forces (SDF), a Kurdish-led militia alliance that holds the quarter of Syria east of the Euphrates, detained Osama al-Awaid last week, it said in a statement.
SDF fighters have been attempting to take Daesh's last Syrian pocket of territory on the banks of the Euphrates near Iraq for weeks, in an offensive backed by US-led air strikes.
They captured Awaid in a special operation in a village in eastern Syria, the statement said, adding that he had been a senior security official for Daesh in the country.
More than a year after Daesh's physical "caliphate" collapsed in both Syria and Iraq under military attack, Baghdadi's whereabouts remains a mystery.
However, despite its loss of territory, the group has been able to launch guerrilla attacks in areas controlled by both the Syrian and Iraqi governments.