“The acts of vandalism against government buildings and PMU offices came as a result of the government’s blatant failure,” Muhandis said in a Sept. 9 statement.

The PMU is an umbrella organization for dozens of mostly Shiite militias, many of which are backed by Iran. Iran and the United States are competing for leverage as Iraq tries to form a new Cabinet, with the United States preferring current Prime Minister Haider al-Abadi, who is seeking a second term. PMU leaders believe their group is a key force in the war against terrorism, as they largely contributed to the defeat of IS , which invaded Iraq and took over a third of its land in 2014.

Protesters on Sept. 7 stormed the PMU office in Basra and set fire to many government buildings, including the Iranian Consulate. The next day, the PMU leadership issued a statement that read, “The deteriorating security situation in Basra calls for the need to protect its people, and the PMU will deal with [the saboteurs] just like it dealt with Islamic State [IS] militants during [previous] battles.” It added, “Ending the security unrest and protecting the lives of citizens is a national and legitimate duty.”

Iraq's Popular Mobilization Units (PMU) are intervening in the violence-plagued southern province of Basra, where demonstrators have been staging mass protests over a lack of public services, the poor economy and alleged corruption among public officials.

Meanwhile, Ali al-Sunaid, a leader of Abadi's Al-Nasr Alliance, accused PMU factions that have joined the Fatah Alliance of burning PMU offices in Basra to create chaos during the protests and to serve their own political agenda against Abadi.

Hisham al-Hashimi, a security analyst at Al-Nahrain Center for Strategic Studies in Iraq, told Al-Monitor, “Security roles in Basra overlap [on three levels]. First, local security is enforced by the local police, the National Security [Council] and the intelligence service in the province [of Basra]. The second [level] is the Basra [security] operation, represented by a branch of the army and federal police in charge of military and security strategies and tactics aimed at imposing stability and enforcing the law when it comes to major incidents that are outside the local security’s scope.”

Hashimi said the third level consists of “tribes, factions and special protection [units] in charge of [safeguarding] party buildings, political and religious figures, and private security companies.” He was referring to the PMU and other armed groups affiliated with the PMU. He expects the PMU to play a greater security role in the near future.

Naim al-Aboudi, spokesman for Asaib Ahl al-Haq (AAH), a PMU-affiliated faction, told Al-Monitor, “PMU factions are ready to play a role in preserving security in the city of Basra and other cities as long as the situation requires it.” He believes the new role stems from “the popular [support] these factions enjoy, as citizens want to feel protected under the PMU." Aboudi added, “If the local police in the cities fail to preserve security, the PMU is ready to take on a security role inside those cities."

Mahmoud al-Robaie, spokesman for AAH's political bureau, agreed, telling Al-Monitor, “The security role is at the core of the PMU’s mission, as PMU [factions] are one of the Iraqi armed forces’ categories. Confronting any attempt to destabilize Iraq is stipulated in the law.”

Robaie said the PMU is needed to preserve security in Basra and other Iraqi cities because of “the prime minister’s poor management of the Basra events." He added, “Police forces acknowledged that the chaos in Basra was due to the failure of the commander of Basra operations to protect the citizens and preserve the safety of public and private properties.”

Ahmad al-Asadi, spokesman for the Fatah Alliance, which is politically allied with the PMU and Iran, told Al-Monitor, “The PMU is closely following up on the security situation, and it will intervene should security deteriorate in Basra or any other city — [the role] is stipulated in the constitution.”

Hashimi said, "The military and security leaders need a monthly assessment of the neutral measures they are implementing in the framework of the constitution and law to preserve security.” However, as the tribes and the PMU are armed, it's important to preserve security without the excessive use of arms to solve any conflict.