“We are aware of the incident, and it is currently under investigation,” Department of Defense spokesman Mark Wright said.
The three under investigation work for the White House Communications Agency, a military operation that sets up secure communications for the president, vice president and Secret Service.
Trump recently visited five Asian nations in 12 days, including a Nov. 10-11 stops in Danang and Hanoi.
This probe comes in the wake of four military members – with the same agency – facing allegations that they brought foreign women into a secure area in Panama after hours, officials said.
The four men involved in the Panama incident, two from the Army and two from the Air Force, were preparing for a trip by Vice President Pence.
They were all sent home before Pence touched down in Panama and taken off their White House gigs, pending the end of a military probe, NBC previously reported.
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