Defense Secretary Lloyd Austin was briefed by his team and is closely monitoring the situation, Kirby said.
The Iraqi military released a statement saying the attack did not cause significant losses and that security forces had found the launch pad used for the rockets. It was found in the al-Baghdadi area of Anbar, an Iraqi military official said on condition of anonymity to discuss the attack with the media.
It was the first attack since the U.S. struck Iran-aligned militia targets along the Iraq-Syria border last week, killing one militiaman and stoking fears of a possible repeat of a series of tit-for-tat attacks that escalated last year, culminating in the U.S. drone strike that killed Iranian Gen. Qassim Soleimani outside the Baghdad airport.
Wednesday’s attack targeted the same base where Iran struck with a barrage of missiles in January last year in retaliation for the killing of Soleimani. Dozens of U.S. service members were injured, suffering concussions in that strike.
British Ambassador to Iraq Stephen Hickey condemned the attack, saying it undermined the ongoing fight against the Islamic State group. “Coalition forces are in Iraq to fight Daesh at the invitation of the Iraqi government,” he tweeted, using the Arabic acronym for IS. “These terrorist attacks undermine the fight against Daesh and destabilize Iraq.”
Denmark, which like the U.S. and Britain also has troops at the base, said coalition forces at Ain al-Asad were helping to bring stability and security to the country.
“Despicable attacks against Ain al-Asad base in #Iraq are completely unacceptable,” Danish Foreign Minister Jeppe Kofod tweeted. The Danish armed forces said two Danes, who were in the camp at the time of the attack, are unharmed.
Wednesday’s attack comes two days before Pope Francis’ is scheduled to visit Iraq in a much anticipated trip that will include Baghdad, southern Iraq and in the northern city of Irbil.
Last week’s U.S. strike along the border had been in response to a spate of rocket attacks that targeted the American presence, including one that killed a coalition contractor from the Philippines outside the Irbil airport.
After that attack, the Pentagon said the U.S. strike was a “proportionate military response” taken after consulting coalition partners.
U.S. troops in Iraq significantly decreased their presence in the country last year under the Trump administration. The forces withdrew from several Iraqi bases across the country to consolidate chiefly in Ain al-Asad and Baghdad.
Frequent rocket attacks targeting the heavily fortified Green Zone, which houses the U.S. Embassy, during President Donald Trump’s time in office frustrated the administration, leading to threats of embassy closure and escalatory strikes.