"At approximately 5:30 p.m. (EST) on January 7, Iran launched more than a dozen ballistic missiles against U.S. military and coalition forces in Iraq," the Pentagon said in a statement.
"It is clear that these missiles were launched from Iran and targeted at least two Iraqi military bases hosting U.S. military and coalition personnel at Al-Assad & Irbil," the statement added.
These bases have been on high alert due to indications that Iran planned to attack the U.S. forces and interests in the region, the statement noted.
The Pentagon also pointed out that it would take all necessary measures to protect and defend U.S. personnel, partners, and allies in the region.
The White House said earlier that it had noticed the reports of attacks on U.S. facilities in Iraq, saying that President Donald Trump is monitoring the situation closely and consulting with his national security team.
The missile attack came hours after Trump's latest warning to Iran earlier in the same day.
"If Iran does anything that they shouldn't be doing, they're going to be suffering the consequences, and very strongly," Trump told reporters in the White House.
Qassem Soleimani, former commander of the Quds Force of Islamic Revolution Guard Corps (IRGC), was martyred in a U.S. airstrike near Baghdad airport on Friday, raising fears of an uncontrolled escalation in the region.
Commander of the IRGC Hossein Salami warned the United States on Tuesday that Iran would take "severe revenge" over its assassination of Soleimani.
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