Kathryn Tyson, Annika Ganzeveld, Ashka Jhaveri, Alexandra Braverman, Andie Parry, and Brian Carter



Information Cutoff: 2:00pm ET

Iranian-backed Iraqi militias may have resumed their attack campaign targeting US forces in Iraq and Syria. Unspecified Iranian-backed Iraqi militia fighters launched at least five rockets from Zummar, Ninewa Province, Iraq, targeting US forces at the Rumaylan Landing Zone in Hasakah Province, Syria, on April 21. The Iraqi government confirmed that unspecified fighters fired rockets at an international coalition base in Syria. The Iraqi government reported that Iraqi security forces burned a vehicle in western Ninewa Province that the fighters had used to launch rockets toward Syria. An unspecified US official separately told Reuters on April 22 that unspecified Iranian-backed Iraqi militants launched at least two drones targeting US forces at Ain al Asad airbase in Anbar Province, Iraq, which is south of the Euphrates River. Iranian-backed Iraqi militia Kataib Hezbollah typically conducts attacks targeting US forces south of the Euphrates River, such as at Ain al Asad airbase in western Iraq and al Tanf Garrison in southeastern Syria. Other militias, including Harakat Hezbollah al Nujaba and Kataib Sayyid al Shuhada, typically conduct attacks targeting US forces north of the Euphrates River. Syrian media reported that the US-led international coalition separately conducted an airstrike targeting a missile launch site in Zummar.

Kataib Hezbollah-affiliated social media channels reportedly announced on April 21 that Kataib Hezbollah had resumed attacks targeting US forces in the region. These channels said that Kataib Hezbollah chose to resume attacks due to Iraqi Prime Minister Mohammad Shia al Sudani’s lack of progress in negotiations to remove US forces from Iraq during Sudani’s recent visit to the United States. Kataib Hezbollah denied on April 21 that it had released such an announcement. The two attacks in Syria and Iraq notably came one day after Sudani returned to Iraq from his visit to the United States.

Kataib Hezbollah previously suspended its attacks targeting US forces in January 2024 following a one-way drone attack that killed three US personnel in northeastern Jordan. US media reported in February 2024 that Kataib Hezbollah “fiercely resisted” IRGC Quds Force Commander Brigadier General Esmail Ghaani’s orders to suspend its attacks. CTP-ISW previously assessed on April 10 that some Iranian-backed Iraqi militias could decide to resume attacks targeting US forces if Sudani’s visit to the United States failed to result in tangible steps toward removing US forces from Iraq.

Key Takeaways:

• Iraq and Syria: Iranian-backed Iraqi militias may have resumed their attack campaign targeting US forces in Iraq and Syria.

• Iran: Hardline Iranian parliamentarian and member of Parliament’s National Security and Foreign Policy Committee Javad Karimi Ghodousi implied that if granted the permission, Iran could test its first nuclear weapon within one week.

• Northern Gaza Strip: Palestinian militias conducted several attacks targeting the IDF in Beit Hanoun in the northern Gaza Strip.

• West Bank: Israeli forces engaged Palestinian fighters in six locations across the West Bank.

• Southern Lebanon and Golan Heights: Southern Lebanon and Golan Heights: Lebanese Hezbollah conducted at least seven attacks from southern Lebanon into northern Israel.

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ISW and CTP has launched an interactive map of Israeli ground operations to accompany our daily campaign assessments of the Israel–Hamas war. This product complements the daily static maps that ISW-CTP produces with high-fidelity and, where possible, street-level assessments of the war in Israel.

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