The human rights watchdog says paramilitary groups should either be integrated into the Iraqi Army's chain of command and held accountable for crimes, or disarmed.
Human rights watchdog Amnesty International released a report on Thursday examining the role of the Iraqi authorities and foreign countries in enabling abuses against civilians by the Popular Mobilisation Units through helping the paramilitary umbrella group acquire weapons.
After the Iraqi Army collapsed in June 2014 as the Daesh terrorist organisation swept through northern Iraq and seized several major cities including Mosul, the government came to increasingly rely on mostly Shia militias organised under the banner of the PMU.
The PMU has been accused of inflaming sectarian tensions by targeting Sunni civilians while retaking territory from Daesh. According to Amnesty, since June 2014, "PMU militias have extrajudicially executed or otherwise unlawfully killed, tortured and abducted thousands of men and boys."
Amnesty also said "Iraqi state institutions have supplied or funded the supply of arms to PMU militias; while other transfers have taken place with the direct or tacit approval of the Iraqi authorities."
To prevent further abuses "the authorities should immediately implement effective command and control over paramilitary militias by Iraqi armed forces, and establish effective oversight and accountability mechanisms by civilian bodies."
In addition, "Any PMU militias that are not thoroughly integrated into the Iraqi armed forces' command and control structures and held fully accountable for human rights violations must be disarmed, demobilised and reintegrated in line with international standards."
Amnesty also found "small-arms and light weapons, rockets, artillery systems and armoured vehicles" from at least 16 countries – including the US, Iran and China – were finding their way into the hands of militia members.
It says foreign states should avoid transferring arms to the Iraqi Armed Forces unless it can be shown the weapons are not at risk of diversion or theft.