A Florida man masturbated during a flight from Spokane to Denver last week, a criminal charge alleges.

Two 18-year-old passengers told an FBI agent that they saw Kyle Devin Pearce, 25, masturbating while on board United Airlines Flight 340 on May 19.

One witness said he was sitting behind Pearce when he saw what he was doing and "hit him with my book in the arm, which caused him to stop and leave to the bathroom. After a while he returned," according to an affidavit. Both witnesses said Pearce's penis was visible.

Pearce was to connect to an Orlando-bound flight but was instead arrested at the airport and appeared before a federal judge in Denver. He posted $25,000 bond Tuesday.

Pearce is charged with crimes aboard aircraft, which carries a maximum 90 days in jail, $5,000 fine and one year probation.