Muhajir was named ISIS spokesperson in 2016 after his predecessor, Abu Mohammad al-Adnani, was killed in a U.S. airstrike, also in Aleppo. Unlike Baghdadi and Adnani, who were known to be Iraqi and Syrian nationals, respectively, and were openly active in Al-Qaeda in Iraq, Muhajir’s identity was publicly unknown, though his nickname—meaning “emigrant”—suggested he may be a foreigner.
The anonymous militant has offered occasional sermons released via audio messages, and was most recently heard in March, breaking nearly six months of silence as the group’s final strongholds in eastern Syria collapsed. Less than a week after his latest message, Trump claimed victory over ISIS.
The moment marked an effective end in the so-called “physical caliphate” phase in the U.S.-led war on ISIS, which lost ground to both the Pentagon-backed Syrian Democratic Forces and a rival campaign waged by the Syrian President Bashar al-Assad, supported by Iran and Russia. Assad was initially the target of CIA intervention in Syria stemming from the early days of the 2011 rebel and jihadi uprising against his rule, but this assistance dwindled as the opposition grew increasingly Islamist and ISIS became a U.S. priority.