The U.S. Embassy in Baghdad was struck by mortar fire Sunday evening in the latest attack on American targets in Iraq, sources told Fox News.

A senior U.S. defense official said all Pentagon officials were safe and accounted for. There were no reported deaths or injuries. The official initially described it as rocket fire, but military sources told Fox News on Monday the attack involved 60-mm mortars, not Katyusha rockets. The sources said of the three mortars fired, one hit the roof of the dining hall, injuring a civilian contractor, one mortar landed short and the third did not explode.

“The security situation remains tense and Iranian-backed armed groups remain a threat. So, we remain vigilant,” a State Department spokesperson told Fox News.

Former Deputy Prime Minister Hoshyar Zebari blamed the attack on an “unruly militia.”

“The Embassy restaurant or canteen was damaged and burned. This is a very dangerous game by #PMF uncontrolled factions to galvanize the tense situation. It must stop,” he tweeted, referring to the Popular Mobilization Forces, an Iranian-backed militia in Iraq.

Separately, five Katyusha rockets crashed into a riverbank in the city's Green Zone without causing any injuries or serious damages, a statement from U.S. Joint Operations Command said.

IRANIAN MISSILE ATTACK ON US BASE IN IRAQ LEFT 34 SOLDIERS WITH CONCUSSIONS, PENTAGON SAYS

Iraq Prime Minister Adel Abdul-Mahdi condemned the attack that targeted the U.S. Embassy. In a statement, he asserted Iraq's commitment to "protecting all diplomatic missions."

The city has been on edge after hundreds of anti-government protesters flooded the streets on Sunday, defying a powerful religious leader who recently withdrew his support from the popular movement.

Anti-government protesters gather in Tahrir Square in Baghdad, Iraq, Sunday, Jan. 26, 2020. (AP)

Security forces fired tear gas and live rounds to disperse the crowds from Baghdad's Khilani Square, medical and security officials said. One protester was killed and six wounded after security forces fired live rounds in nearby Wathba Square later in the evening.

Iraqi security forces reportedly wounded at least 28 demonstrators in the first hours of Sunday's street rallies.

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Sunday’s attack came after Iran launched ballistic missiles on two military bases in Iraq where U.S. troops have been stationed, in retaliation for a drone strike that killed Qassem Soleimani, Iran’s top military general. Dozens of troops were said to have been diagnosed with brain injuries, but no one was killed in the attacks.

Fox News' Nick Kalman and The Associated Press contributed to this report.