US Secretary of Defence Lloyd J. Austin III said the U.S. military forces conducted self-defence strikes on the direction of President Joe Biden.

Austin said in a statement: "These precision self-defense strikes are a response to a series of ongoing and mostly unsuccessful attacks against U.S. personnel in Iraq and Syria by Iranian-backed militia groups that began on October 17."

" As a result of these attacks, one U.S. citizen contractor died from a cardiac incident while sheltering in place; 21 U.S. personnel suffered from minor injuries, but all have since returned to duty," he said.

Austin said the President has no higher priority than the safety of U.S. personnel, and he directed the action to make clear that the United States will not tolerate such attacks.

Austin said: "These narrowly tailored strikes in self-defence were intended solely to protect and defend U.S. personnel in Iraq and Syria."

He said the attacks are separate from ongoing conflict between Israel and Hamas.