Washington (ANN)- Protesters enraged by US airstrikes on Iraq staged a violent demonstration outside the US Embassy in Baghdad on Tuesday, setting fires ablaze and hurling stones as security forces and guards fired tear gas and stun grenades to repel them.

In Washington, US President Donald Trump accused Iran of orchestrating the violence and said Tehran would be held responsible. More US troops were being sent to the embassy, US officials said.

The protests were led by Iranian-backed militias and lasted several hours, but the US State Department said later that personnel was secure and the facility had not been breached.

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A State Department spokesperson said reports from Iraqi officials that the ambassador had been evacuated were false. The envoy, Matt Tueller, had been on previously scheduled personal travel and was returning to the embassy, the official said. There were no plans for an evacuation.

The demonstration appeared to be an escalation of the proxy conflict between Washington and Tehran – a hugely influential player in Iraq – while mass protests are challenging Iraq’s own political system nearly 17 years after the US invasion that toppled Saddam Hussein.

It also shifted the focus of the mass protests away from the government and pro-Iran militias, and on to the United States.

US airstrikes on Sunday on Iranian-backed militia bases killed at least 25 fighters and wounded 55.

Those raids, on the Kataib Hezbollah militia, responded to the killing of a US civilian contractor in a rocket attack on an Iraqi military base.

“Iran killed an American contractor, wounding many. We strongly responded, and always will,” Trump said in a tweet. “Now Iran is orchestrating an attack on the US Embassy in Iraq. They will be held fully responsible.”

The protesters, including militiamen, torched a security post at the entrance of the embassy, Reuters witnesses said. The protesters threw stones at the gate while others chanted, “No, no, America! No, no, Trump!”

Iraqi special forces were deployed around the main gate to prevent protesters entering. US-trained and -equipped Iraqi Counter-Terrorism forces later reinforced them.

Medical sources said 12 militiamen were wounded by the tear gas and stun grenades fired to disperse the crowd.

The Washington Post reported that US diplomats and staffers were huddled in a fortified safe room in the embassy, according to two reached by a messaging app.

A few hours into the protest, some of the militias encouraged protesters through loudspeakers to leave.

“We have delivered our message, please leave the area to avoid bloodshed,” one announcement said.

READ: Iran denies involvement in targeting US forces in Iraq

Security guards inside the embassy also fired stun grenades at protesters outside the gates of the compound. Reuters correspondents heard at least seven loud bangs.

A Reuters witness saw blood on the face of one wounded militiamen and on the stomach of the other as their colleagues carried them away.