Deir ez-Zor offensive (September–November 2017)

Deir ez-Zor offensive
	Part of the Battle of Deir ez-Zor and the Eastern Syria campaign of the Syrian civil war
	; The situation in Deir ez-Zor, as of 17 November 2017 Syrian Government control Syrian Democratic Forces control
Date	14 September – 17 November 2017; (2 months and 3 days)
Location	Deir ez-Zor, Deir ez-Zor Governorate, Syria
Result	Syrian government victory
Territorial; changes	On 17 October, the Syrian Army secured a perimeter surrounding the ISIL-controlled half of the city; On 3 November, the Syrian Army took complete control of the city, and on 17 November, ISIL surrendered the island of Hawijat Kati, bringing all areas around the city under Army control;
Belligerents
Syrian Government; Russia; Iran; Allied militias:; Liwa Fatemiyoun; Fatah al-Intifada; Galilee Forces; Free Palestine Movement	Islamic State of Iraq and the Levant
Commanders and leaders
Maj. Gen. Suheil al-Hassan; Maj. Gen. Issam Zahreddine †; (Republican Guard); Lt. Gen. Valery Asapov †; (Syrian 5th Corps); Brig. Gen. Ghassan Iskandar Tarraf; (Republican Guard); Tha'er Ismail †; (Tiger Forces); Maj. Gen. Abu Ali Salhab; (Military Security Shield Forces); Tariq al-Hassan †; (Baqir Brigade); Shaaban Ali Amiri †; (IRGC senior commander)	Unknown
Units involved
Syrian Armed Forces Syrian Arab Army Republican Guard 104th Airborne Brigade; ; 17th Reserve Division 137th Mechanized Brigade; ; Tiger Forces; ; Syrian Arab Air Force; National Defense Forces; Military Intelligence Directorate Military Security Shield Forces; ; Local Defence Forces Baqir Brigade; Lions of Hussein; ; ; Russian Armed Forces Russian Air Force; Russian Navy; Special Operations Forces; Wagner Group; ; IRGC;	Military of ISIL Wilayat Deir ez-Zor; ;
Casualties and losses
120 killed (18 Sep. – 25 Sep.; 29 Oct. – 1 Nov.)	300+ killed (Syrian claim; 29 Sep. – 13 Oct.); 101 killed (per SOHR; 29 Oct. – 1 Nov.); 250+ captured

The Deir ez-Zor offensive was a military operation launched by the Syrian Armed Forces to completely expel the Islamic State of Iraq and the Levant (ISIL) from the city of Deir ez-Zor, a provincial capital, located on the banks of the Euphrates river. From 2014 until 2017, the city had been divided into Syrian government and ISIL-controlled halves. The rest of the Governorate (province) was under ISIL control for most of this time, putting the government-controlled half of the city under siege.

In the summer of 2017, the Syrian Army launched a large-scale offensive in central Syria, where they succeeded in lifting the siege and began offensive operations to capture the rest of the city, as well as the surrounding areas.