Iraqi protesters burned tires on three bridges Saturday in the southern city of Nasiriyah, despite the prime minister's announcement that he will step down from office.
Adel Abdul-Mahdi said Friday he will submit his resignation to the country's parliament, following weeks of deadly protests.
The people responsible for the killings must be brought to justice, Iraq's semi-official Human Rights Commission said in a statement Saturday.
"Firearms and live ammunition must only be used as a last resort," the International Committee of the Red Cross warned in a statement.
Abdul-Mahdi's announcement Friday came after Iraq's top Shiite cleric called for a change in leadership in the country. At least 400 people have been killed and hundreds of others wounded since anti-government protests began October 1.
"I will submit to parliament an official memorandum resigning from the current prime ministry,'' the Abdul-Mahdi said, in response to the cleric's call. He did not specify when he will step down.
The move triggered celebrations by protesters in Baghdad's Tahrir Square, however demonstrators said they would continue their sit-in at the square
Iraq’s parliament is set to hold an emergency session on Sunday to discuss the crisis.
Earlier on Friday, during his weekly sermon, Grand Ayatollah Ali Al-Sistani urged Iraq's parliament to reconsider its support for Abdul-Mahdi's government, amid the rising violence.
Violence continued on Friday with medical officials saying at least three protesters were shot by security forces in the southern city of Nasiriyah.
On Thursday, Iraqi security forces used live ammunition against mostly unarmed demonstrators in Nasiriyah, killing at least 40 people in one of the bloodiest days since anti-government protests began last month, security and medical officials said.
At least 25 people were killed and more than 200 wounded when security forces opened fire on protesters who had blocked key roads and bridges in the city.
Baghdad said it had sent military troops to restore order across southern Iraq, where protests have grown increasingly violent. Demonstrators have occupied buildings and bridges and have clashed with security forces, who have used tear gas and live ammunition almost daily since protests began.
Amnesty International denounced the violence in Nasiriyah, calling it a bloodbath.
In Baghdad, security forces shot and killed four people Thursday and wounded at least another 22 as protesters tried to cross the Ahrar Bridge, which leads to the Green Zone, the heavily fortified seat of Iraq's government.
The demonstrators are demanding an end to government corruption and what they perceive as increasing Iranian influence in Iraqi affairs.