More than 70 others were wounded by gunfire and stabbings near Tahrir Square, the main protest camp in the Iraqi capital, police and medics said according to Reuters.
It was the most violent flare-up in the capital for weeks and came a week after Iraqi’s prime minister, Adil Abdul Mahdi, said he would resign following two months of anti-government protests.
Security sources said they could not identify the gunmen who attacked protesters.
Sistani has repeatedly condemned the killing of unarmed protesters and has also urged demonstrators to remain peaceful and stop saboteurs turning their opposition violent.
Sistani, Iraq’s most senior Shia cleric, has long opposed any foreign interference.
He only weighs in on politics in times of crisis and holds enormous sway over public opinion.
“We hope a new head of government and its members will be chosen within the constitutional deadline” of 15 days since the resignation was formalized in parliament on Sunday, a representative of Sistani said in his Friday sermon in the holy city of Karbala.
“It must also take place without any foreign interference,” he said, adding that Sistani would not get involved in the process of choosing a new government.
The burning of Iran’s consulate in the holy city of Najaf, the seat of Iraq’s Shia clergy, and subsequent killings of protesters by security forces in southern cities paved the way for Sistani to withdraw his support for Abdul Mahdi.
Abdul Mahdi pledged to step down last week after Sistani urged lawmakers to reconsider their support for the government following two months of anti-establishment protests where security forces have killed more than 400 demonstrators.
More than a dozen members of the security forces have been killed in the clashes.
Washington on Friday imposed sanctions on three Iraqi paramilitary leaders who it accused of directing the killing of Iraqi protesters. A senior US Treasury official suggested the sanctions were timed to distance those figures from any role in forming a new government.
A senior State Department official lambasted his involvement in establishing the next Iraqi government. “Seems to us that foreign terrorist leaders, military leaders, should not be meeting with Iraqi political leaders to determine the next premier of Iraq,” David Schenker, Assistant Secretary for Near Eastern Affairs at State Department, told a briefing.
Abdul Mahdi and his government will stay on in a caretaker capacity until a new government can be chosen, the prime minister said last week.
President Barham Salih officially has 15 days - until Dec. 16 - to name a new premier tasked with forming a government that would be approved by parliament up to a month later.
Iraqi lawmakers say they will then move to hold a general election next year but protesters say that without a new, fully representative electoral law and unbiased electoral commission, a snap vote will keep corrupt politicians in power.
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