At least four militiamen were killed on Thursday in the southern Iraqi city of Basra during fighting between rival Shiite factions, days after deadly clashes in Baghdad amid a continuing political crisis.
The men were from two arch foes, the Saraya Al Salam armed militia that is tied to populist cleric Moqtada Al Sadr, and the Iran-backed Asaib Ahl Al Haq militia led by Qais Al Khazali.
They each lost two fighters in the gun battle.
The clashes drew strong condemnation from Mr Al Sadr's representative Mohammed Saleh Al Iraqi, who lashed out at Mr Al Khazali.
“I warn you, Qais! If you do not restrain your insolent militias and if you do not absolve yourself of the murderers and criminals that are affiliated to you … you too are insolent,” he said in a statement on Twitter.
In response, Mr Al Khazali ordered the shut down of all his militia offices across the country until further notice.
He also instructed his supporters to ignore “insults” against him to avoid an escalation.
“I ask our brothers in Asaib Ahl Al Haq to close all offices of the movement immediately and until further notice,” he said on Twitter.
“If they want to burn them, let them, and don't give it any further thought”, he said.
Mr Al Iraqi released another statement on Thursday evening with follow-up demands addressed to caretaker prime minister Mustafa Al Kadhimi, saying that Iran-linked groups must leave the Green Zone, the flashpoint for Monday's deadly violence.
He also said the chairman of the Popular Mobilisation Forces, a collection of militias linked to the government but in many cases backed by Iran, must resign. Faleh Al Fayyadh, who is currently in this role, is an influential figure in Shiite politics in Baghdad.
Asaib Ahl Al Haq and Kataib Hezbollah have stationed fighters in and around the sprawling Green Zone, which hosts the parliament, residences of the elite and foreign embassies.
Analysts say on several occasions those fighters have been used to intimidate Mr Al Kadhimi's government and they are suspected of firing on Mr Al Sadr's supporters on Monday, during a chaotic three-way battle between the official army and the rival militias.
Violence had escalated after Mr Al Sadr ordered his followers to reinforce a sit-in outside the parliament building, blocking his rival political coalition, the Co-ordination Framework, from convening to form government.
A funeral is expected to be held for the Saraya Al Salam fighters in Basra late on Thursday.
Soon after the fighting erupted security forces were deployed to the location, and Basra's governor Assad Al Eidani said on Thursday that the situation in the city was now “safe and under control”.
Earlier in the day the spokesman's office of the Iraqi army said there were conflicting reports on social media of security incidents and unrest in Basra governorate.
“We would like to point out that the issue is about the existence of a murder incident in the centre of the governorate that also left another injured, where the security forces arrested a number of suspects and are carrying out their duties and investigating this incident,” the authorities said on Thursday.
Heavy gunfire could be heard in video footage taken early on Thursday in the area near the Italian Bridge over the Shatt Al Arab river.
Basra, Iraq’s southern oil centre, has historically been a flashpoint for rivalry between Shiite groups. In July 2018, protesters demonstrated near major oilfields to demand more jobs and basic services.
Iraq, which has been dominated by sectarian politics since the US toppled dictator Saddam Hussein, has been without a government since a general election last October due to a stand-off between Mr Al Sadr and pro-Iran factions.
Tension escalated sharply on Monday when Mr Al Sadr announced his withdrawal from politics. His supporters reacted by storming a government palace in Baghdad's high-security Green Zone. At least 30 people were killed in the ensuing violence.
Mr Al Sadr had been demanding the dissolution of parliament and new elections.
His rivals in the pro-Iran Co-ordination Framework want a new head of government to be appointed before any new elections are held.
The two sides are in disagreement over the appropriate mechanism to dissolve parliament and hold early elections, key demands of Mr Al Sadr.
The populist cleric's party received the most votes in the election but was not able to reach the legislative quorum to vote in a government that excluded his Iran-friendly rivals.
The Supreme Court session that was expected to rule on whether the judiciary can dissolve parliament has been postponed until next Wednesday.
A negative ruling is expected to elicit a reaction from the cleric.