Flag of the Syrian Armed Forces. The flag is the flag of the Syrian Arab Republic with the Coat of Arms of the Syrian Armed Forces in the top left hand corner. Across the top the flag says "Homeland Honor Devotion" (وطن شرف إخلاص), and "Syrian Arab Army" (الجيش العربي السوري) across the bottom.
Own work. Based on flag visible in videos here,here, and here, here, here, and here.
MrPenguin20