Baghdad – The State Department issued a security alert overnight telling all Americans in Iraq to leave the country immediately.

"U.S. citizens should depart via airline while possible, and failing that, to other countries via land," it said. "Due to Iranian-backed militia attacks at the U.S. Embassy compound, all public consular operations are suspended until further notice. U.S. citizens should not approach the Embassy."

The alert was issued shortly after Qassem Soleimani, the head of Iran's elite Quds military force and one of the most powerful figures in the Islamic Republic, was killed Thursday night in an airstrike in Baghdad. The Pentagon said President Donald Trump ordered the "decisive defensive action to protect U.S. personnel," accusing Soleimani of "actively developing plans to attack American diplomats and service members in Iraq and throughout the region."

His death ignited a new chapter of regional tensions. Iran's Supreme Leader Ali Khamenei took to Twitter and vowed severe revenge. And Iraq's prime minister said the assassinations are a massive breach of sovereignty and the security agreement with the United States now needs revaluation.

American allies in the region like Israel are preparing for possible retaliation and are on high alert, CBS News' Ian Lee reports. So are American forces – with 9,000 in the region and 3,000 extra preparing to deploy.



Iraqi counter-terrorism forces stand guard in front of the U.S. embassy in the capital Baghdad on January 2, 2020. AHMAD AL-RUBAYE/AFP via Getty Images

Hours before the killings, U.S. troops from the Army's 82nd Airborne Division arrived in Kuwait.

The question isn't whether Iran will strike back, but rather how, and to what severity, and when it's over, will the killing of Soleimani have been worth it, Lee reported.

On Friday morning, Iran-backed Hezbollah ordered its "resistance fighters" around the world to avenge Soleimani.

Soleimani is a polarizing figure in Iraq, and his death further exposed the deep divides on the country's streets. In Baghdad's Tahrir Square, anti-government protesters celebrated the news of his death, accusing Soleimani of being behind the deaths of many demonstrators in recent months.