What Is Kataib Hezbollah? Iraq’s Iran-Backed Militia Explained

Kataib Hezbollah is the most powerful of the Iraqi militias aligned with Iran, and the one most closely tied to the Quds Force, the Revolutionary Guards’ foreign arm. It formed between 2005 and 2007 out of the small “special groups” the Quds Force ran against American troops after the 2003 invasion, when five of those cells merged under one name.

Its founder and commander was Abu Mahdi al-Muhandis, an Iraqi who also held Iranian citizenship and who said openly that the group relied on Iran for weapons, advice and planning. Its leadership council is chosen with the Quds Force’s approval, and it takes Iran’s Supreme Leader, Ali Khamenei, as its spiritual guide. The group wants an Iranian-style Islamic government and the departure of U.S. forces from the region.

No. Kataib Hezbollah is an Iraqi organization, separate from Lebanon’s Hezbollah, though the two share a name, an ideology and a patron. Lebanese Hezbollah instructors trained some of its fighters in Iran in the 2000s.

The real difference is where each one sits. Lebanon’s Hezbollah is a political party with its own army. Kataib Hezbollah operates inside the Iraqi state: its fighters serve in three brigades of the Popular Mobilization Forces, the 45th, 46th and 47th, which Baghdad pays, and its members hold the security, intelligence and missile departments of that state-funded umbrella force.

Ahmad al-Hamidawi, known as Abu Hussein, has been secretary-general since 2020. He took over after a U.S. drone strike near Baghdad airport killed al-Muhandis together with the Quds Force commander, Qassem Soleimani, on January 3, 2020.

Washington designated al-Hamidawi a terrorist in February 2020, and on April 14, 2026 the State Department offered up to $10 million for information on him. It says he directed the group’s attacks on U.S. diplomatic sites in March 2026. The group has also lost commanders: a U.S. strike in Baghdad killed its operations chief for Syria, Abu Baqir al-Saadi, on February 7, 2024, and on March 16, 2026 the group announced the death of its security chief, Abu Ali al-Askari, during the wave of strikes on Iraqi militias in the Iran war.

Nobody outside the group knows its exact size, and published estimates run from about 1,000 to 30,000 fighters. The 30,000 figure is the group’s own claim from December 2014, when Iraqi militias were mobilizing against the Islamic State group.

Specialist estimates are much lower. Detailed profiles of the group judge that it has probably never had more than about 10,000 fighters, including some 2,500 once sent to Syria, and one 2024 assessment put it near 8,000, with the number actually under arms likely smaller than the salaries it draws from the state budget. Silent Dossier’s judgment is that a figure in the high thousands, with a much smaller core of trained missile and drone crews, fits the record best.

It has attacked Americans since the U.S. occupation of Iraq, and its deadliest attacks have drawn direct U.S. strikes in return. On December 27, 2019, a rocket attack on the K-1 base near Kirkuk killed a U.S. civilian contractor; the United States bombed the group’s sites, and its supporters then stormed the outer compound of the U.S. Embassy in Baghdad on December 31, 2019.

On January 28, 2024, a drone hit Tower 22, a small U.S. outpost in northeast Jordan, killing three American soldiers and wounding more than 30. The Pentagon said the attack bore Kataib Hezbollah’s “footprints,” the United States struck the group in Iraq and Syria, and on January 30, 2024 Kataib Hezbollah announced it was suspending operations against U.S. forces.

After the U.S.-Israeli war on Iran began on February 28, 2026, Iraqi militias including Kataib Hezbollah attacked U.S. sites in Iraq again, and U.S. aircraft struck their bases. The group’s reach now extends abroad: on May 15, 2026, U.S. prosecutors charged Mohammad Baqer al-Saadi, whom they describe as a Kataib Hezbollah commander, with helping to organize at least 18 attacks in Europe and Canada and a plot against a New York synagogue. The November 10 indictment over RAF Fairford adds him as a defendant. The charges are allegations that have not been tested in court, and Iran denies a role.

Yes. The group has paused attacks but has refused to disarm. The U.S.-led coalition completed its withdrawal from Iraq on September 30, 2026, when the last American forces and equipment left Erbil Air Base in the Kurdistan Region, and the same day al-Hamidawi ordered his fighters to halt military operations, except against hostile aircraft in Iraqi airspace, until the government completes its own air defenses.

On October 1, al-Hamidawi denied reaching any disarmament deal with Prime Minister Ali al-Zaidi. “The resistance has won this round,” he said, adding that the group’s weapons “will remain as a trust in the hands of our mujahideen.” Al-Zaidi has promised serious steps to bring all weapons under state control, and some militias say they have done so, but Kataib Hezbollah and Harakat Hezbollah al-Nujaba have not. Germany’s exit from the same mission is covered in Germany’s Iraq Mandate Outlasts Its Deployment, and the reach of the missiles Iran supplies its allies is set out in How Far Can Iran’s Missiles Reach?