Some of the casualties were airlifted to bases in Germany and Kuwait where they continue to recover. Officials initially said there were no injuries in the airstrike which was launched in retaliation for a US drone strike in Baghdad that killed Qassem Soleimani, the commander of the elite Quds Force of Iran’s Revolutionary Guard.
Donald Trump and the US military had said there were no casualties after the strike on the Ain al-Asad air base in western Iraq and a facility in its northern Kurdish region.
But in a statement today, Captain Bill Urban, spokesman for US Central Command, said: “While no US service members were killed in the January 8 Iranian attack on al-Asad air base, several were treated for concussion symptoms from the blast and are still being assessed.
“As a measure of caution, some service members were taken to US facilities in Germany or Kuwait for follow-on screening.
“When deemed fit for duty, the service members are expected to return to Iraq.”
As many as 1,500 Americans were deployed at the vast base deep in Iraq’s Anbar desert.
There were fears Iran’s retaliatory strike would spark all-out military conflict in the strife-torn Middle East but both sides scaled down the rhetoric in the wake of the attack.
Today, Iran’s supreme leader Ayatollah Ali Khamenei branded Mr Trump a “clown” who only pretended to support the Iranian people.
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Addressing Friday prayers in Tehran for the first time since 2012 the Ayatollah said Mr Trump would “push a poisonous dagger” into the nation’s back.
He said the outpouring of grief at Gen Soleimani’s funeral showed Iranians supported the Islamic Republic.
And he said the Ain al-Asad missile attack was a “blow to America’s image” as a superpower.
The White House has since imposed crippling sanctions on Iran, including its vital oil and gas industry, pushing the country into an economic crisis that has ignited several waves of sporadic, leaderless protests.
Mr Trump has openly encouraged the protesters, even tweeting in Farsi, hoping that the protests and the sanctions will bring about fundamental change in a long-time adversary.