A Massachusetts man faces a federal charge for allegedly sexually assaulting a 19-year-old woman sitting next to him on a flight bound for Dulles International Airport last summer.

An FBI affidavit reviewed by the News4 I-Team says George Seryogin assaulted the woman, whom he met in row 26 of a United Airlines flight from Tokyo to Dulles.

Seryogin allegedly began by touching her knee, then began sexually groping her, the affidavit says. He placed a blanket over her leg, making it difficult for other passengers to see him.

The affidavit said "the victim was also quietly crying, with tears streaming down her face" and pushed his hands off her.

"My client firmly denies the allegations against him," said Seryogin's attorney, Mary M. Nerino. She offered no additional comments.

United Airlines said in a statement it banned Seryogin from flying with them.

"The safety and well-being of our customers is our top priority. Our customer was immediately moved to a different seat when the flight attendant was made aware of the issue and we requested law enforcement meet the aircraft on arrival," the statement said. "We will continue to fully cooperate with law enforcement’s investigation and the perpetrator has been banned from flying United. Sexual harassment, inappropriate behavior, intimidation or predation have absolutely no place anywhere in our society — including in our industry and on our aircraft."

A grand jury has indicted Seryogin on a federal criminal charge. He faces one count of abusive sexual contact aboard an aircraft in flight. He was set to appear in court Friday for arraignment. Seryogin's case will be prosecuted at the federal court in Alexandria.

Seryogin is a dual citizen of Russia and the U.S.

This is not the first such allegation on a local flight.

An I-Team review of federal court records revealed at least four other sex assault cases aboard flights to Dulles or Reagan Washington National Airport since 2013.

The FBI has posted warning signs on TV monitors at Dulles International, which say sex assaults aboard flights are federal crimes.

The FBI's DC field office has an airport liaison team assigned to handle airborne crimes.