Abu Mohammad al-Jolani, the leader of Hayat Tahrir al-Sham, last year in the village of Besnaya, in Syria’s northwestern Idlib Province. Omar Haj Kadour/Agence France-Presse — Getty Images ...

Baridi, known as "The Uncle", was purportedly shown in a video this year pledging allegiance to Islamic State's leader Abu Bakr al Baghdadi. But the Yarmouk Martyrs Brigade have publicly denied ...