Pentagon Deploying Extra Troops to Baghdad After Attack by Protesters

"The Department of Defense is working closely with the Department of State to ensure the security of our Embassy and personnel in Baghdad," Esper said in a statement on Tuesday.

"We are sending additional forces to support our personnel at the embassy,” he added.

On Tuesday, the US embassy was evacuated after thousands of angry Iraqi demonstrators gathered outside the gates of the compound to condemn Washington’s fatal military aggression that targeted Iraq’s Popular Mobilization Units (PMU) on Sunday.

On Monday, Iraqi Prime Minister Adel Abdul Mahdi condemned the "unacceptable vicious assault" by the US that killed more than two dozen Iraqis and injured scores more.

Thousands of angry protestors managed to reach the US diplomatic mission which is located in Baghdad's heavily fortified Green Zone, chanting “Death to America” and burning US flags.

The protesters further held up signs calling for the US mission to be shut down and for the parliament to order US forces to leave Iraq.

“Parliament should oust US troops, or else we will,” one poster read.

Reuters cited two Iraqi Foreign Ministry sources as saying that the US ambassador and other staff were evacuated from the embassy out of security concerns as protests raged outside.

Only a few embassy protection staff were left behind, according to the news agency.

American forces deployed inside the compound have fired tear gas, flash bangs and stun grenades to disperse the crowd.