US President Donald Trump ordered the killing of Iran Revolutionary Guards commander Qasem Soleimani, who died in Baghdad "in a decisive defensive action to protect US personnel abroad," the Pentagon said on Friday.
"General Soleimani was actively developing plans to attack American diplomats and service members in Iraq and throughout the region. General Soleimani and his Quds Force were responsible for the deaths of hundreds of American and coalition service members and the wounding of thousands more," the Department of Defense said.
It said that attack was aimed at deterring future Iranian attack plans.
Following Soleimani's death, Trump tweeted an image of the US flag without any further explanation.
Earlier, the Hashed military force had said that 'US strike' had killed top Iran and Iraq commanders at Baghdad airport.
The Hashed is a network of mostly-Shiite armed units, many of whom have very close ties to Tehran, who have been officially incorporated into Iraq's state security forces.
General Qassim Soleimani, the head of Iran's elite Quds Force, was killed in an airstrike at Baghdad's international airport.
The strike also killed Abu Mahdi al-Muhandis, the deputy commander of Iran-backed militias known as the Popular Mobilization Forces, or PMF, the officials said.
Iran's Revolutionary Guards confirmed in a statement read out on state television that the commander of its Quds unit Qasem Soleimani was killed by US forces in Baghdad on Friday.
Their deaths are a potential turning point in the Middle East and are expected to draw severe retaliation from Iran and the forces it backs in the Middle East against Israel and American interests.
(With agency inputs)
