﻿An Iraqi interior ministry spokesman has said an investigation is underway to determine how protesters were shot dead during six days of unrest that have killed more than 100 people and injured thousands.

Twelve anti-government demonstrators were killed on Sunday in ongoing protests in Baghdad. Saad Maan, a spokesman for the ministry, claimed on Sunday that security forces did not confront the protesters, adding that “malicious hands” were behind targeting protesters and security members alike. He said protesters had burned 51 public buildings and eight political party headquarters.

Protesters and journalists on the scene say they witnessed security forces firing on demonstrators with some saying snipers were taking part. Maan said most of those killed on Friday were hit in the head and heart.

Protests have raged in Baghdad and southern cities since Tuesday. Maan said 104 people, including eight security force members, had been killed and more than 6,100 wounded, including more than 1,200 security members.

On Sunday, army soldiers fired in the direction of about 300 anti-government protesters who gathered in a suburb of the Iraqi capital.

Facebook Twitter Pinterest Iraqi security forces fire tear gas at protesters. Photograph: Hadi Mizban/AP

The demonstrators, mostly young men, were scattered in side streets near Sadr City. Troops blocked the main road preventing them from advancing and fired above their heads.

Iraq’s prime minister, Adel Abdul-Mahdi, called on Saturday for an end to the protests, saying he was ready to meet protesters to hear their demands. He said there were orders for the security forces not to use live ammunition except in strict cases of self-defence.

Security forces are “trying to carry out their duties” and have also incurred casualties. Abdul-Mahdi said the violence has been “reciprocated” and promised an investigation to determine who had been firing live ammunition.

“We can’t accept the continuation of the situation like this,” Abdul-Mahdi told his cabinet on Saturday. “We hear of snipers, firebombs, burning a policeman, a citizen.” He added that “not a political party office” or government office has been spared attacks.

“I am ready to go wherever our brotherly protesters are and meet them or send them envoys to other locations without any armed forces,” Abdul-Mahdi said. “I will go and meet them without weapons and sit with them for hours to listen to their demands.”

He announced a list of executive decisions focusing on providing housing for those on low incomes, unemployment benefits and vocational training. He also decreed that those killed in the protests, whether demonstrators or security, would be considered “martyrs” eligible for state benefits.

The unrest is the most serious challenge facing Iraq two years after the victory against Islamic State militants. The chaos also comes at a critical time for the government, which has been caught in the middle of increasing tensions in the region, chiefly between Iran and the US. Iraq is allied with both countries and hosts thousands of American troops, as well as powerful paramilitary forces linked with Iran.

The UN envoy for Iraq appealed for an end to the violence and called for holding to account those responsible. “This must stop. I call on all parties to pause and reflect,” Jeanine Hennis-Plasschaert tweeted on Saturday night.