Nearly three dozen US troops have been diagnosed with concussions or traumatic brain injury since the Jan. 7 Iranian ballistic missile strikes against Iraqi bases housing American forces, the Pentagon’s top spokesman said today.

Of the 34 US forces injured in the strike, exactly half have returned to duty, chief Pentagon spokesman Jonathan Hoffman said. Meanwhile, eight American service members arrived in the United States for further screening this morning, while another nine are still receiving treatment in Landstuhl, Germany.

The public controversy over the injuries has prompted Defense Secretary Mark Esper to direct the Joint Staff and Matt Donovan, who is performing the duties of the Pentagon’s top personnel and readiness officer, to review the process for determining casualties in the field. Esper was only informed of the evacuations after at least 11 US troops had left Iraq, the Pentagon has said.

But the new reporting represents a reversal for the administration, which initially said no Americans had been hurt in the attack. President Donald Trump at first had insisted the United States had “suffered no casualties” in the strikes in a White House address the morning after 10 Iranian rockets struck Ain al-Asad air base, where the commander in chief made his first overseas visit to meet American forces in 2018. On Wednesday, the president downplayed the injuries, describing them as “not very serious.”