As many as 550 protesters have been killed in Iraq since protests began in October, the Iraqi Commission for Human Rights revealed on Monday. Overall figures are likely higher, because the data only begins on October 30 and many protesters were killed in October. The report reveals that 22 people have been murdered in assassinations. Many of these killings were carried out by Iranian-backed militias, operating with impunity against the protesters.Since October Iraq has tried to blame a “third party” for killing protesters. But many protesters have clashed with elements of the Popular Mobilization Units (PMU) which are a group of mostly Shi’ite militias, many linked to Iran and the Islamic Revolutionary Guard Corps. The US has accused Qais Khazali of Asaib Ahl Al-Haq of being one of those behind suppressing protests. Other groups within the PMU such as Kataib Hezbollah, Saraya al-Khorasani and Hadi al-Amiri’s Badr have also been involved. Protesters have targeted the offices of these militias. The militias gained strength after 2014 when many young men joined to fight ISIS. But after the war on ISIS largely ended in 2017, the PMU used its forces to punish the Kurdistan region for an independence referendum, taking over Kirkuk. They also took over rural areas around Sunni cities, setting up checkpoints. They have been accused of numerous abuses, as well as operating secret prisons and trafficking weapons to Syria and Hezbollah in Lebanon via their own storehouses. Abu Mahdi al-Muhandis, then the leader of Kataib Hezbollah, established offices in Syria and bases, and Qais Khazali went to Lebanon to threaten Israel in 2017. The US killed Muhandis on January 3 alongside IRGC commander Qasem Soleimani.The PMU have played a key role suppressing protesters, often using snipers and plain-clothed men with guns. Protesters have shown videos of these attacks. In recent weeks, Iraqi political leader Muqtada al-Sadr has begun working with the PMU and Badr to arrange anti-US protests. None of the protesters linked to Sadr or Badr were killed on December 31 or January 23 in mass rallies, showing that it is only the other protesters, many of them critical of Iran, who are targeted. This means that Iranian-backed militias are likely behind hundreds of deaths in Iraq. Sadr has now called for an end to the protests, which could lead to a new crackdown.