WASHINGTON • Charging that Iran was "fully responsible" for an attack on the United States Embassy in Iraq, President Donald Trump ordered about 750 US soldiers to be deployed to the Middle East as about 3,000 more prepared for possible deployment in the next several days.
No US casualties or evacuations were reported after the attack on Tuesday by dozens of Iran-supported militiamen.
US Marines were sent from Kuwait to reinforce the compound.
Meanwhile, US troops guarding the Baghdad embassy yesterday fired tear gas as hundreds of Iran-backed militiamen and other protesters gathered outside for a second day and set fire to the roof of a reception area inside the compound.
The crowds of men brandished the colours of Iraq's pro-Iranian force Hashed al-Shaabi, set US flags on fire and hurled rocks towards the compound. The US Marines guarding the embassy fired the tear gas as more crowds arrived and after the roof of the reception area was set alight.
At least 20 people were wounded, the Hashed said. The protesters fully withdrew from the embassy later yesterday.
US Defence Secretary Mark Esper said on Tuesday night that "in response to recent events" in Iraq, and at Mr Trump's direction, he authorised the immediate deployment of the infantry battalion from the US Army's 82nd Airborne Division at Fort Bragg, North Carolina.
He did not specify the soldiers' destination, but a US official familiar with the decision said they will go to Kuwait.
Mr Esper said in a written statement: "This deployment is an appropriate and precautionary action taken in response to increased threat levels against US personnel and facilities, such as we witnessed in Baghdad today."
Additional soldiers from the 82nd Airborne's quick-deployment brigade, known officially as its Immediate Response Force, were prepared to deploy, Mr Esper said.
The US official, who provided unreleased details on condition of anonymity, said that the full brigade of about 4,000 soldiers may deploy. The 750 soldiers deploying immediately were in addition to 14,000 US troops who had deployed to the Gulf region since May in response to concerns about Iranian aggression, including its alleged sabotage of commercial shipping in the Persian Gulf.
At the time of the attack, the US had about 5,200 troops in Iraq, mainly to train Iraqi forces and help them combat Islamic State in Iraq and Syria extremists. The breach of the US Embassy compound in Baghdad on Tuesday was a stark demonstration that Iran can still strike at American interests despite Mr Trump's economic pressure campaign.
It also revealed growing strains between Washington and Baghdad, raising questions about the future of the US military mission there.
"They will pay a very big price! This is not a warning, it is a threat. Happy New Year!" Mr Trump tweeted on Tuesday afternoon, though it was unclear whether his "threat" meant military retaliation.
He thanked top Iraqi government leaders for their "rapid response upon request".
American air strikes on Sunday killed 25 fighters of an Iran-backed militia in Iraq, the Kataib Hizbollah. The US said those strikes were in retaliation for last week's killing of an American contractor and the wounding of American and Iraqi troops in a rocket attack on an Iraqi military base that the US blamed on the militia.
The American strikes angered the Iraqi government, which called them an unjustified violation of its sovereignty. While blaming Iran for the embassy breach on Tuesday, Mr Trump also called on Iraq to protect the diplomatic mission.
Even as Mr Trump has argued for removing US troops from Middle East conflicts, he also has singled out Iran as a malign influence in the region.
After withdrawing the United States in 2018 from an international agreement that exchanged an easing of sanctions for curbs on Iran's nuclear programme, Mr Trump ratcheted up sanctions.
Those economic penalties, including a virtual shut-off of Iranian oil exports, are aimed at forcing Iran to negotiate a broader nuclear deal. But critics say that pressure has pushed Iranian leaders into countering with a variety of military attacks in the Gulf.
ASSOCIATED PRESS, AGENCE FRANCE-PRESSE