An Iraqi security source told CNN that in recent weeks nearly 5,000 fighters from Iranian-backed paramilitary groups in Iraq crossed into Iran through two southern Iraqi border crossings—the Shaib crossing in Maysan Province and the Zurbatiya crossing in Wasit Province—to assist with the ongoing crackdown on anti-government protests in Tehran and elsewhere in Iran.

A European military source separately confirmed that about 800 Shiite militia fighters traveled from the Iraqi provinces of Diyala, Maysan, and Basra to support the Iranian crackdown. The fighters reportedly belong to Tehran-aligned armed groups, including Kataib Hezbollah, Harakat Hezbollah al-Nujaba, Kataib Sayyid al-Shuhada, and the Badr Organization, all operating under the umbrella of Iraq’s Popular Mobilization Forces (PMF).