On Jan. 15, the Islamic State launched a new offensive in Deir Ezzor. The eastern Syrian city has been divided between the so-called caliphate and Bashar al Assad’s regime since July 2014. In the two and half years since, the jihadists and Assad’s loyalists have regularly clashed, leading to an ongoing humanitarian crisis.

The situation has become even more dire in recent days. Despite fighting on multiple fronts throughout Iraq and Syria, the Islamic State was able to muster enough forces for a significant push into the city.

According to the UN Office for the Coordination of Humanitarian Affairs (OCHA), Abu Bakr al Baghdadi’s men have “effectively cut the besieged enclave in two.” Deir Ezzor’s airport and two neighborhoods in the east have been cut off from the city’s more populous western neighborhoods.

An OCHA map of the current situation in Deir Ezzor can be seen above.

An estimated 93,500 people, “including over 40,000 children,” live in the parts of the city controlled by the Assad regime. The Islamic State’s prolonged siege has deprived them of “regular access to food, medicines and other essentials” since mid-2014. For months, humanitarian organizations delivered provisions and foodstuffs “through high altitude air drops.” But the Islamic State’s new assault on Deir Ezzor has made that impossible, according to OCHA, as the jihadis have taken “control of the drop-zone which is located three kilometers west of the airport.” The offensive has only exacerbated the ongoing crisis, with regular shortages in the supply of food, water, medicines, electricity and other necessary items.

Islamic State propaganda from the offensive

The Islamic State frequently clashes with the Assad regime, as well as allied militias and conscripts, in Deir Ezzor.

Amaq News Agency, one of the Islamic State’s chief propaganda outlets, has eagerly advertised the exchanges, using captured regime fighters and militiamen in its videos. The captives are often made to renounce the Assad regime. Amaq has also provided a steady stream of other videos and images, including clips of the jihadis using anti-tank weapons against regime tanks and other assets.

An infographic produced by Amaq in early January listed 1,112 “martyrdom operations” (suicide attacks) in Iraq and Syria throughout 2016. Thirty-six (36) of these bombings supposedly took place in Deir Ezzor province. Although suicide bombers are deployed more regularly in other areas of Syria, Deir Ezzor was still tied with Raqqa for the third most frequently targeted province. Only the Aleppo (150) and Hasakah (49) provinces witnessed more suicide bombings, according to Amaq.

Amaq has published numerous videos and photos from the recent offensive. On Jan. 16, the propaganda outlet said that the jihadis had captured key positions “west of the Deir Ezzor airbase,” destroying a bus that was “transporting troops and three other vehicles” during the battle. The airbase quickly came under siege from “all sides,” according to Amaq, and approximately 40 Syrian troops were killed during the early hours of the fighting.

On Jan. 18, Amaq announced that Islamic State fighters had captured “the electrical substation, its checkpoint” and a plaza “northwest of the airbase.” This was reportedly followed by advances on “the Syrian army field hospital,” and other key points. An Amaq video contained footage from inside the hospital, a crude facility with pockmarks from mortar shells and other ammunition scattered throughout the walls.

Other Amaq statements on Jan. 19 and Jan. 20 claimed that the jihadis have destroyed a “field artillery piece” and a tank belonging to the Syrian regime.

Russian warplanes have run bombing missions over the city in support of the Syrian Army, as well as the irregulars who have been pressed into service. An Amaq video released on Jan. 21 purportedly showed the destruction caused by the Russian bombings, with buildings reduced to rubble. A screen shot from the video can be seen above.

Continuous fighting between Islamic State, Assad regime in Deir Ezzor

The Syrian Observatory for Human Rights (SOHR) has published regular reports on the fighting in and around Deir Ezzor since 2014. But the Islamic State’s offensive in the city appears to be its most significant effort in the area since early 2016.

During a press briefing on Jan. 29, 2016, Colonel Steve Warren, who was then the spokesman for Operation Inherent Resolve (OIR), discussed the Islamic State’s operations in Deir Ezzor.

Col. Warren said that the city was “split” between the Islamic State and the regime, with each controlling about 50 percent. The jihadists had been “battling regime forces” for some time, Warren noted, but used “the cover a sandstorm” to gain ground in “single neighborhood.” This temporarily increased the Islamic State’s control “from 50 percent to maybe 56 percent,” but the Assad regime “gained some of it back when the weather cleared and they were able to bring some air power to bear.” In Warren’s view, the Islamic State’s short-lived gains did not amount to a “major tactical event.” Other accounts claimed that the jihadis massacred civilians and Syrian forces during the Jan. 2016 raid.

The two sides continued to clash in and around Deir Ezzor in the year since.

During a press briefing on Aug. 16, 2016, Colonel Christopher Garver, another OIR spokesman, confirmed that the city was still “divided.” The Islamic State had been in the city for “many months” at that point, with the US flying missions against the group both inside Deir Ezzor and in the area around it. The US and its allies had “certainly attacked a lot of the oil infrastructure…outside of Deir Ezzor and in that area,” Garver said. Meanwhile, the Islamic State and the Syrian Army had “been fighting over that city for quite a long time.”

The Islamic State has earned significant oil revenues from wells outside of Deir Ezzor city. And as Garver explained, the oil fields have been a frequent American target. The US has continued to bomb oil wells and related infrastructure even as the jihadis surged in the city this month.

The US air campaign in Deir Ezzor led to an international incident in Sept. 2016, when American bombers mistakenly struck fighters allied with the Syrian regime. According to the Defense Department, the Americans believed they were bombing Islamic State positions, an indication of just how close the front lines between the two sides were at the time. Indeed, the two foes have been at each other’s throats in Deir Ezzor for two and a half years.

Thomas Joscelyn is a Senior Fellow at the Foundation for Defense of Democracies and the Senior Editor for FDD's Long War Journal.

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