The Pentagon revealed Friday that a total of 34 US service members have been diagnosed with concussions and traumatic brain injuries since the Jan. 8 Iranian ballistic missile attack.

Immediately after the missile attack, President Donald Trump announced that "no Americans were harmed."

As reports of injuries began to trickle out, the president downplayed the severity of the injuries, telling reporters that they are "not very serious."

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The Department of Defense told reporters Friday that nearly three dozen US service members have been diagnosed with traumatic brain injuries in the aftermath of the Iranian missile attack on US forces in Iraq earlier this month, according to multiple reports.

The Pentagon, following repeated questions, revealed Friday that a total of 34 US service members have been diagnosed with concussions and traumatic brain injuries, some of whom were flown to Germany and the US for treatment. (The Pentagon is reportedly using those two terms interchangeably).

The department said that the delays in reporting the TBIs is that these injuries are not always immediately apparent. "Some of these conditions manifest over time, symptoms can get better and get worse. This is a snapshot in time," Pentagon spokesman John Hoffman explained.

A concussion is a type of traumatic brain injury — damage affecting the brain's normal function caused by a sudden blow to the head or the severe shaking of the head and body.

Immediately following the Jan. 8 ballistic missile attack on US and coalition forces at Al Asad Air Base and in Irbil, President Donald Trump proudly announced that "no Americans were harmed."

A little over a week later, US Central Command revealed that there were, in fact, injuries.

"While no U.S. service members were killed in the Jan. 8 Iranian attack on Al Asad Air base, several were treated for concussion symptoms from the blast and are still being assessed," CENTCOM spokesman Capt. Bill Urban explained in a statement.

He said that a total of 11 US service members had to be transported to facilities in Germany and Kuwait for additional screening and treatment.

On Tuesday, Jan. 21, The Washington Post reported that the number was higher, although it did not give a specific number.

When questioned Wednesday about his earlier statement, now known to be inaccurate, Trump downplayed the severity of the injuries, saying they are "not very serious."

"I heard that they had headaches and a couple of other things, but I would say and I can report that it's not very serious," the president told the press in Davos, Switzerland. "I don't consider them very serious injuries relative to other injuries that I've seen."

When an Associated Press reporter asked for more information about these injuries on Jan. 23, a CENTCOM spokesman told him they'll no longer "play this game."