The US military launched an airstrike against a hospital in eastern Mosul that was used as a command center by the Islamic State as Iraqi troops failed to seize the complex over the past several days. The strike highlights the difficulties ahead in retaking the city, as the Islamic State remains entrenched.

US Central Command, or CENTCOM, announced the strike, which took place on Dec. 7, and explained the circumstances behind the operation. The US military is sensitive to hitting protected targets such as hospitals; an accidental strike on a Médecins Sans Frontières-run hospital in Kunduz, Afghanistan in October 2015 killed 42 people and sparked international condemnation.

“The Coalition complies with the Law of Armed Conflict and takes all feasible precautions during the planning and execution of airstrikes to reduce the risk of harm to non-combatants,” CENTCOM stated.

According to CENTCOM, Islamic State fighters were using the Al Salem hospital complex as “a base of operations and command and control headquarters.” Iraqi troops, likely US-trained special forces that have spearheaded the assault to retake Mosul, “attempted to seize” the hospital on Dec. 6, but Islamic State fighters counterattacked.

Iraqi troops were hit with six suicide car bombs “before retrograding a short distance,” or retreating, according to CENTCOM. The US military then “conducted a precision strike on the location to target enemy fighters firing on Iraqi forces” on Dec. 7.

The Islamic State has put up significant resistance to defend Mosul, Iraq’s second largest city. The jihadist group has deployed scores of suicide car bombs during the fighting. Mosul, which fell in June 2014, is the last major city held by the Islamic State. Abu Bakr al Baghdadi, the group’s emir, announced the formation of the Islamic State and the establishment of the “caliphate” in a mosque in Mosul in June 2014.

The Iraqi military’s assault on the Al Salem hospital is reminiscent of a failed operation by Iraqi special forces to retake the city of Tikrit in late June 2014. Iraqi commandos air assaulted behind Islamic State lines and captured buildings at Tikrit University, only to withdrawal two days later after coming under fierce attacks. At least one Iraqi helicopter was shot down during the operation. The Islamic State held Tikrit until April 2015.

While the Iraqi military suffered a setback at the Al Salem hospital, the US military said that the Islamic State has been surrounded in both Mosul and Tal Afar.

“Mosul is effectively isolated now,” Captain Jeff Davis, a Pentagon spokesman, told reporters during a briefing on Dec. 7. “They [the Islamic State] still have freedom of movement between Mosul and Tal Afar, but they don’t have freedom of movement beyond Tal Afar and into Syria.”

Iranian-supported Shiite militias, including Hezbollah Brigades, a US-designated Foreign Terrorist Organization, have cut off Tal Afar from Syria and are also operating southwest of Mosul.

“This is hard fighting, but the fact remains that ISIL is surrounded,” David continued “They’re facing resistance from within the city, they’re being bombarded daily by coalition air and artillery strikes, they have no ability to resupply or reinforce, and it is a military fact that they are in a position where defeat is inevitable.”

But the fight to retake Mosul will be “very slow and methodical,” David concluded.

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

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