The attorney for the suspect said it was a misunderstanding, saying his client thought he was getting a cheap airline ticket, not a fake one.
A man who toured the Capitol was found with a gun on Tuesday, officials said.
Thieves broke into the grounds of Windsor Castle, King Charles' residence west of London, and stole two vehicles from royal land, police said, in a major breach of security.
Iranian hackers sought unsuccessfully to interest President Joe Biden's campaign in information stolen from rival Donald Trump's campaign, federal agencies said.
The unidentified passenger was escorted off the plane and according to the TSA, there was no security violation since he had a valid ID and boarding pass for a different flight that day.
New footage shows passenger successfully board wrong flight as new details emerge about security breach