FBI: Man Assaulted Flight Attendant on Christmas Eve Flight Into Dulles

The FBI says a passenger suspected of heavy drinking assaulted a flight attendant and threatened air marshals aboard a Christmas Eve flight to Washington Dulles International Airport, the News-4 I-Team has learned.

Air marshals handcuffed the man, placed a seat belt on him and taped it closed to try to prevent him from unbuckling it, but he managed to break free and “act aggressively” toward the marshals, court filings by investigators say.

According to an affidavit filed by the FBI, an air marshal watched a German-speaking Swiss national named Martin Sievert “walk erratically” from a bathroom to his seat on a United Airlines flight from Zurich to Dulles on Dec. 24.

Sievert was "staggering and swaying back and forth with bloodshot eyes," the marshal reported.  

The court filing said a flight attendant then noticed an open bottle of duty-free liquor and a can of beer near Sievert at his seat. The FBI agent, in the court filing, said a flight attendant seized the alcohol, but that Sievert went to the back of the plane and retrieved it and then and assaulted the flight attendant.

According to the court filing, “Sievert jumped up and grabbed [the flight attendant] by the shirt collar and pulled him back, assaulting him.”

Air marshals handcuffed Sievert and strapped him into his seat belt, the FBI agent said. But “Sievert continuously struggled and was able to unbuckle himself and act aggressively," the court document says.

The flight landed safely about 3 p.m. The plane was immediately boarded by agents with U.S. Customs and Border Protection and the Metropolitan Washington Airports Authority police, who helped place the passenger under arrest, according to court filings.

A United Airlines representative said in a statement, "We are cooperating with authorities who met the aircraft upon its arrival at Dulles." 

The Metropolitan Washington Airports Authority did not immediately respond to requests for comment.

Sievert was ordered held in jail Tuesday by a federal judge. He appeared in court in Alexandria, Virginia, Wednesday morning and pleaded guilty to a misdemeanor charge. A court docket lists the charges as simple assault and interference with a flight crew. 

United Airlines has banned Sievert for life, the court document say.

Information on Sievert's lawyer was not available immediately. 

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