Washington Post: The disclosure comes after 3 US troops were killed in a strike on Jordan.

These are the first American service members killed due to direct Iranian fire since the opening days of the war.

US and Iran have stepped up attacks in the last week, prompting alarm about return to full-scale war across the region.

Four other troops taken to Jordanian hospitals and later discharged

Over 400 US military personnel have been injured since the war broke out months ago