For the second time this month, the US military targeted an Islamic State chemical weapons facility in northern Iraq. The Islamic State has pursued a chemical weapons program in both Iraq and Syria, which has been targeted by the US since it launched its air campaign in the summer of 2014.

On Sept. 23, US warplanes bombed “an ISIL [Islamic State] chemical weapons factory” near the town of Qayyarah, US Central Command, or CENTCOM, reported. Iraqi forces gained control of Qarrayah and the nearby Qayyarah Airfiled West, or Q-West, from the Islamic State in mid-July.

The Qayyarah chemical factory is the second chemical facility targeted by the US military in the past two weeks.

On Sept. 14, US warplanes targeted “an ISIL chemical weapons storage facility and destroyed a rocket system, a rocket rail, and a mortar system,” near the Iraqi town of Huwayjah.

In addition to targeting chemical facilities, the US military has focused on key leaders and experts in the Islamic State’s chemical weapons program. On May 18, the US military announced that it killed Abu Sufyan, who was described as “a senior chemical expert who staged chemical attacks in the Euphrates River Valley” in Anbar province, Iraq.

In February, the US military announced that it captured Sulayman Dawud al Bakkar, the Islamic State’s “’emir’ of chemical and traditional weapons manufacturing,” during a raid in Iraq.

“His capture removed a key ISIL leader from the battlefield and provided the coalition with important information about ISIL’s chemical weapons facilities, production, and the people involved,” the US military noted at the time of his capture.

In January 2015, US forces killed Abu Malik, an Islamic State “chemical weapons engineer,” in an airstrike near Mosul.

The US military’s pursuit of the Islamic State’s chemical weapons program in Iraq has become even more important after US forces based at Q-West were targeted with a shell containing “a sulfur-mustard blister agent,” General Joseph Dunford, the Chairman of the US Joint Chiefs of Staff, told the Senate Arms Services Committee on Sept. 22, according to USA Today.

Al Qaeda in Iraq, the forerunner of the Islamic State, has used crude chemical weapons against US forces during the occupation. The Long War Journal has recorded 12 chemical attacks, mostly with chlorine gas, in Baghdad, Anbar, and Diyala provinces during 2007.

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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