More than 100 members of the US military are now known to have suffered traumatic brain injuries following an Iranian missile attack last month.
The latest figure released by the Pentagon represents a jump of over 50% on the 64 who were reported as having TBI about a week ago.
And Pentagon officials have warned the number would continue to change.
Of the 109 confirmed cases, 76 have now returned to duty.
Some 26 others are in Germany or the US for treatment, and another seven are on their way from Iraq to Germany for evaluation and treatment.
Iran launched more than a dozen ballistic missiles targeting the al-Asad installation and another air base near Irbil in northern Iraq.
All is well! Missiles launched from Iran at two military bases located in Iraq. Assessment of casualties & damages taking place now. So far, so good! We have the most powerful and well equipped military anywhere in the world, by far! I will be making a statement tomorrow morning.
— Donald J. Trump (@realDonaldTrump) January 8, 2020
Both bases were “hosting US military and coalition personnel”, according to the Pentagon.
The attack was in retaliation for America’s killing of Iran’s top general Qassem Soleimani in a drone strike at Baghdad airport on 3 January.
Immediately after the air base assault by Tehran, President Trump tweeted no US troops had been hurt.
Later in January he appeared to play down the brain injuries, saying he “heard that they had headaches and a couple of other things”, sparking criticism from politicians and a US veterans group.
Pentagon officials have repeatedly said there has been no attempt to minimise or delay information on concussive injuries.
But the disclosures following Tehran’s attack have led to renewed questions over the US military’s policy about how it internally reports suspected brain injuries.
And whether they are treated publicly with the same urgency as loss of limb or life.
US Republican Senator Joni Ernst has demanded more answers.
She tweeted: “I’ve called on the Pentagon to ensure the safety and care of our deployed forces who may be exposed to blast injuries in Iraq.”
Defence Secretary Mark Esper has said the Pentagon was studying ways to prevent brain injuries on the battlefield and to improve diagnosis and treatment.
Army general Mark Milley, chairman of the Joint Chiefs of Staff, said it is possible, in some cases, that symptoms of TBI from the Iranian missile attack will not become apparent for a year or two.
He said the army was in the early stages of diagnosis and therapy for the troops.