Separately, at least one of five Katyusha rockets fired at Baghdad’s fortified Green Zone hit the US embassy, wounding three people, in a rare direct targeting of the compound, security sources said.

The US State Department said in a statement there have been 14 attacks on US personnel in Iraq since September.

It also called on Iraq to “fulfil its obligations to protect our diplomatic facilities”.

“The security situation remains tense and Iranian-backed armed groups remain a threat,” the statement read. “So we remain vigilant.”

Anti-government protests erupted in Baghdad on October 1 and quickly turned violent. Security forces and unidentified gunmen have shot protesters dead. Nearly 500 people have been killed in the unrest.

The protests are an unprecedented leaderless challenge to Iraq’s Shi’ite Muslim-dominated and largely Iran-backed ruling elite, which emerged after a US-led invasion toppled Sunni dictator Saddam Hussein in 2003.

Demonstrators are demanding that all parties and politicians be removed, free and fair elections be held and corruption rooted out. The government has responded with violence and piecemeal reform. The international community has condemned the violence but not intervened to stop it.

In Baghdad, one protester was killed, police sources and medics said, and more than 100 others hurt across the country after the security forces tried to clear protest camps.

At least 75 of those hurt were in the southern city of Nasiriyah.

A witness said protesters set fire to two security vehicles and hundreds of other demonstrators controlled key bridges in the city. Later, unidentified men set fire to tents that are part of a months-long sit-in in the city centre. Protests have flared in the last two days after populist cleric Moqtada al-Sadr, many of whose supporters had participated, said he would no longer be involved in anti-government demonstrations.

Sadr opposes all foreign interference in Iraq but has aligned himself more closely in recent months with Iran and the Tehran-backed parties that dominate state institutions in Baghdad.

Some demonstrators have accused the populist cleric of treachery of their cause. Sadr has organised separate anti-American demonstrations aimed at pressuring US troops to leave Iraq, moves that critics say aim to eclipse the anti-establishment movement which has taken aim at all politicians including Sadr.

The increase in unrest comes after Washington killed Iranian Major-General Qassem Soleimani, the mastermind of Iran’s control over Iraq, and an Iraqi paramilitary chief in a drone strike in Baghdad on January 3. Iran responded with ballistic missile attacks on two Iraqi military bases, but the killing has revived tensions in Iraqi politics and delayed the formation of a new government.

Five Katyusha rockets hit Baghdad’s Green Zone, which houses government buildings and foreign embassies, late on Sunday, a military statement said. It did not report casualties.