They were on their way to Ukraine to take part in Exercise Saber Guardian that began July 20.

The incident took place on July 19, but was only reported to the media a fortnight later.

The servicemen, traveling from Alaska, reportedly had problems with a connecting flight at Vienna's Schwechat Airport and had to leave the transit area to rebook, Austrian Defense Ministry spokesman Colonel Michael Bauer said. They were traveling on commercial flights.

While they were having their luggage scanned, airport security spotted M16 assault rifles and pistols in their travel bags. The servicemen had no permits allowing them to carry arms.