BAGHDAD (AP) — A U.S. contractor died Wednesday when at least 10 rockets slammed into an air base housing U.S. and other coalition troops in western Iraq, the Pentagon said.

Pentagon spokesperson John Kirby said the contractor “suffered a cardiac episode while sheltering” and died shortly afterward. He said there were no service members injured and all are accounted for.

The rocket attack was the first 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.-directed strike that killed Iranian Gen. Qassim Soleimani outside the Baghdad airport.

No one claimed responsibility for Wednesday’s attack, which comes two days before Pope Francis is scheduled to visit the country amid concerns about security and the coronavirus pandemic. The much-anticipated trip will include stops in Baghdad, southern Iraq and the northern city of Irbil.

The rockets struck Ain al-Asad airbase in Anbar province early in the morning, U.S.-led coalition spokesperson Col. Wayne Marotto said. Kirby said the rockets were fired from east of the base.

In addition to American troops, Danish and British are among those stationed at the base. It’s the same base that Iran struck with a barrage of missiles in January of last year in retaliation for the killing of Soleimani. Dozens of U.S. service members suffered concussions in that strike.

The Iraqi military released a statement saying that Wednesday’s attack did not cause significant losses and that security forces had found the launch pad used for the rockets — a truck. Video of the site shows a burning truck in a desert area.

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 said coalition forces at the base 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.

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 strike was a “proportionate military response” taken after consulting coalition partners.

Marotto, the coalition spokesperson, said the Iraqi security forces were leading an investigation into the attack.

Frequent rocket attacks targeting the heavily fortified Green Zone, which houses the U.S. Embassy, during Donald Trump’s presidency frustrated the administration, leading to threats of embassy closure and escalatory strikes. Those attacks have increased again in recent weeks, since President Joe Biden took office, following a lull during the transition period.

U.S. troops in Iraq significantly decreased their presence in the country last year and withdrew from several Iraqi bases to consolidate chiefly in Ain al-Asad, Baghdad and Irbil.

Reporting by AP’s Samya Kullab from Baghdad and Lolita C. Baldor. Jan M. Olsen in Copenhagen contributing. Trademark and Copyright 2021 The Associated Press. All rights reserved.