US condemns 'excessive' use of force in Iraq
Security forces opened fire last week on demonstrators in the southern city, killing at least 29 people and wounding dozens more, according to security and medical sources.
The deaths of protesters came amid an uptick in violence last week after demonstrators in the Shia holy city of Najaf torched the Iranian consulate.
The subsequent crackdown on protesters claimed nearly 70 lives in Najaf, Nasiriyah and the capital Baghdad and led the country's foremost Shia Muslim authority to call on the government to step down.
Iraqi Prime Minster Adel Abdul Mahdi announced his intention to resign on Friday, a move that was ratified by parliament on Sunday.
More than 420 protesters have been killed since the demonstrations against corruption, economic mismanagement and foreign influence erupted in early October.
"The use of excessive force over the weekend in Nasiriyah was shocking and abhorrent," David Schenker, US assistant secretary of state for Near Eastern affairs, said on Tuesday according to Reuters.
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"We call on the Government of Iraq to respect the rights of the Iraqi people and urge the government to investigate and hold accountable those who attempt to brutally silence peaceful protesters."
Iraq's Sairoon party, backed by influential cleric Moqtada al-Sadr, has also called for the government to try those responsible for the crackdown.
MP Sabah Al-Saadi on Sunday urged the judiciary to form a court specialised, in what he dubbed the "October Revolution", to hold to account the outgoing prime minister and security leaders for the violent crackdown on demonstrators across the country.
He also called for imposing travel bans on Abdul Mahdi and security leaders.
The violent crackdown also drew condemnation from Pope Francis over the weekend.
"I am following the situation in Iraq with concern. It is with pain that I have learned of the protest demonstrations of the past days that were met with a harsh response, causing tens of victims," he said.
The protests have largely been limited to Baghdad and the country's Shia-majority south, but spread over the weekend to Sunni-majority western and northern provinces as protesters gathered across the country to mourn those killed.
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