Abu Omar al-Shishani

Tarkhan Tayumurazovich Batirashvili, known by his nom de guerre Abu Omar al-Shishani or Omar al-Shishani, was a Georgian-Chechen jihadist who, as one of the Chechen mujahideen in Syria, served as the leader of the Muhajireen Battalion before defecting and becoming a commander for the Islamic State, and was previously a sergeant in the Georgian Army.

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