A man has been arrested for allegedly masturbating while sitting next to a woman on board a Southwest Airlines flight from Seattle to Phoenix on Saturday.

According to court documents, the man, identified as Antonio Sherrodd McGarity did not only touch himself "inappropriately," but also exposed himself. He "exposed his penis and masturbated while in view of the female passenger sitting next to him," read the court documents.

McGarity allegedly pulled down his pants and started touching himself within the first hour of the flight. The woman informed the flight crew immediately after the man fell asleep. She had even taken pictures of the act as evidence and gave them to the crew. She was later moved to another seat for the remainder of the flight.

"Shortly after taking off, and while the aircraft was in the air, McGarity exposed his penis by pulling down his pants and shorts and began masturbating," the criminal complaint states. "She suspected that McGarity ejaculated because he licked a white substance from his fingers," it added.

FBI officials questioned McGarity, who admitted to masturbating during the flight. He said that he was aware of the fact that the woman sitting next to him could see him.

He added that he had asked the female passenger "if she minded if he masturbates," and that "the female witness put her hands in the air and said, 'It really doesn't matter.'"

The man assumed that response was "kind of kinky" and believed she was comfortable with him masturbating, added the complaint, per a report by Newsweek.

Southwest Airlines has imposed a lifetime ban on McGarity and has confirmed the reports about the incident. "On April 2, we received reports of inappropriate Customer behaviour on flight 3814 from SEA to PHX. The situation was reported to Crewmembers while inflight, and the Captain contacted law enforcement to meet the aircraft upon arrival," said a Southwest spokesperson.

"We immediately placed the passenger on our No-Fly List, resulting in a lifetime ban from traveling on Southwest."

Southwest Airlines
Southwest Airlines. Photo: AFP / Robyn Beck