Last June, as the Iraqi security forces advanced into the mainly Sunni city of Fallujah, the US urged al-Abadi to delay the assault until his army could prepare escape routes for civilians. Instead, I was told, al-Abadi rushed into battle and allowed two armed Shiite groups, Asaeb Ahl al-Haq and Kataeb Hezbollah—both of which receive funding from Iran and have links to the Islamic Revolutionary Guard Corps in Tehran—to occupy important exit points from the city. The Shiite militias abducted as many as seven hundred Sunni men and boys who were attempting to flee from the village of Saqlawiyah, just north of the Fallujah. “Some of them were killed. Some of them were buried alive,” al-Mutlik told me.

Other Sunni captives freed by these paramilitary groups around Fallujah described atrocities—including beatings, torture, and imprisonment in squalid warehouses. Many Shiite militiamen, al-Mutlik said, were taking revenge for the executions of Shiite cadets by the Islamic State near Tikrit in 2014. Al-Mutlik said he has confronted al-Abadi in his office “numerous times” and begged him to curb the Shiite Popular Mobilization Forces (PMF). “I told him, ‘you are the commander-in-chief of the Iraqi forces. The militias have kidnapped hundreds of innocent people. What is your role?’ He replied simply, ‘These militias have embarrassed me so much.’”

The Western diplomat who observed the Fallujah battle told me that the US moved quickly to stop the bloodshed between Shiites and Sunnis. “When we found out that there had been abuses, we stepped in right away,” the diplomat said. “The Iraqi government made several arrests, and we don’t think those abuses continued.” Mueen al-Kadume, a leader in Baghdad of the Shiite Badr Brigades, now one of the partners in the Popular Mobilization Forces, blamed the Fallujah killings on a “few individuals.” In other Sunni areas, he said, “the people have experienced that the Al-Hashd al-Sha’abi—the Popular Mobilization Forces—is keen to protect them.”

Yet the Shiite militias have acted violently against the Iraqis quite aside from their killings in Fallujah. In the ethnically mixed town of Tuz Khormato, fifty-five miles south of Kirkuk—in a territory disputed between the Kurdish-administered north and the Iraqi central government—Shiite fighters marched into town last spring and began fighting both with the peshmerga and the ethnic Kurds who supported them. “The Shia militia would kill me the minute they see me,” one Kurdish resident told Al Jazeera. “Some [Kurds] have lost their lives only because of who they are, and those who are still alive cannot reveal their identity.”