Two U.S. officials said U.S. personnel were injured in a ballistic missile attack on Al-Asad air base in Iraq on Saturday.
The attack resulted in minor injuries, officials said, although it was not immediately clear how many people were injured.
U.S. Central Command confirmed the attack Saturday evening and said in a statement that “a number” of U.S. personnel were being evaluated for traumatic brain injuries.
Several ballistic missiles and rockets targeted the base and while most were intercepted by the base's air defenses, some hit the CENTCOM statement said.
The use of more powerful ballistic missiles, which are far rarer than rockets or single-use attack drones, comes at a time of rising tensions in the region, with the war between Israel and Hamas already 100 days old.
U.S. and coalition forces have faced increasing threats from Iran-backed Shiite militias since the start of the war. As of Thursday, U.S. and coalition forces had been attacked more than 143 times in Iraq and Syria since October 7; Saturday's incident appears to be the second use of ballistic missiles to attack the United States.
The Islamic Resistance of Iraq, an Iran-backed militia group, claimed responsibility for Saturday's attack.
In a statement, the group stressed its commitment to resisting American “occupying forces” in the region and described the attack as a response to what it described as a “Zionist entity massacre” against the Palestinian people in Gaza. The company provided no evidence to support its claim.
In November, militants in Iraq fired short-range ballistic missiles at coalition forces, prompting the U.S. to conduct airstrikes against facilities belonging to the Iran-backed group Kataib Hezbollah, which was responsible for many of the missile and drone attacks against the coalition.
US forces in Iraq and Syria are part of the coalition fighting ISIS. But the Iraqi government has called for the final withdrawal of international forces from the country after US strikes on Kataib Hezbollah facilities – the Biden administration's first strikes in Iraq since the war began in Gaza – raised tensions with the Iraqi government had.
“We believe that a reset of relations by ending its presence will prevent further tensions and intertwining of internal and regional security issues,” Iraqi Prime Minister Mohammed Shia al-Sudani told Portal earlier this month.
The UN Secretary-General's special representative for Iraq also warned that the region was at a “critical juncture” with the war in Gaza, saying in a statement that Iraq risked being drawn even further into the conflict .
“Despite the government’s efforts to prevent an escalation of tensions, persistent attacks – from inside and outside Iraq’s borders – threaten to undermine the country’s hard-won stability and the gains it has made in recent years,” the statement says.
The Pentagon has maintained that its military presence is still at the invitation of the Iraqi government and nothing has changed. National security adviser Jake Sullivan met with al-Sudani in Davos, Switzerland, earlier this week and the two discussed the “importance of maintaining a strong bilateral partnership,” the White House said in a readout.
Separately, the United States also faces threats in the Red Sea and the Gulf of Aden. Iran-backed Houthi rebels have launched repeated attacks on international shipping lanes, including at least two attacks on U.S. ships this week, causing some of the world's largest shipping companies to avoid the critical waterway.
The U.S. has carried out a series of increasingly frequent attacks against Houthi assets, and President Joe Biden said Thursday that attacks will continue but acknowledged that U.S. strikes have not deterred the group's attacks.
CNN's Kaanita Iyer, Mohammed Tawfeeq, Hamdi Alkhshali, Haley Britzky and Donald Judd contributed to this report.