A disturbing in-flight assault case has led to criminal charges after a passenger on an international flight was accused of sexually assaulting a sleeping woman while other passengers watched in shock.
Authorities say witnesses, including a flight attendant, stepped in after allegedly seeing the suspect repeatedly touch the sleeping passenger during a long-haul flight to Florida.
Passenger Charged After Alleged Sexual Assault on International Flight
Forty-eight-year-old Guillaume Sebastien Roger Mattler, a resident of France, is now facing a federal criminal charge of abusive sexual contact.
According to investigators, the alleged assault happened aboard a commercial international flight traveling from Zurich to Miami.
The criminal complaint was filed in the Southern District of Florida.
Incident Happened in First-Class Cabin
Authorities say Mattler was traveling in the first-class cabin on Swiss International Air Lines Flight LX64.
According to investigators, the suspect briefly spoke with the 29-year-old woman seated next to him before she turned away, curled up in her seat, and fell asleep.
Witnesses say the situation became disturbing midway through the flight.
Witnesses Allegedly Saw Repeated Inappropriate Contact
According to court documents, one passenger reportedly saw Mattler touching the woman’s lower back while she slept.
Witnesses allegedly said:
- He first made it appear accidental
- He touched her again for a longer period
- He appeared to move his hand toward private areas
- His movements appeared deliberate
Another passenger reportedly described the movement as a “submarine” motion.
Flight Attendant Allegedly Witnessed Assault
After passengers raised concerns, a flight attendant reportedly approached the seats to investigate.
According to investigators, the crew member allegedly saw Mattler:
- Touching the woman over her jeans
- Making rubbing or scooping motions
- Touching her intimate area while she slept
The flight attendant immediately intervened.
Suspect Moved After Witnesses Intervened
When confronted, investigators say Mattler could not show any proof that he knew the woman.
Flight staff then removed him from first class and moved him to economy seating for the rest of the flight.
Authorities say the woman remained asleep during most of the incident.
Suspect Later Returned With Disturbing Note
According to investigators, Mattler was later escorted back to his original seat area to collect personal belongings.
At that time, police say he allegedly attempted to hand the woman a handwritten note.
The note reportedly said:
“You look beautiful when you are sleeping.”
This reportedly added to investigators’ concerns about his intentions.
Victim Was Shocked After Learning What Happened
After the flight crew woke the woman and explained what witnesses had seen, authorities say she was visibly shaken.
Investigators say she:
- Confirmed she did not know Mattler
- Became emotional
- Started crying
- Appeared deeply shocked
Suspect Later Admitted Touching Victim
After the flight landed in Miami, authorities interviewed Mattler.
Investigators say he initially denied touching the woman.
However, after being informed about:
- Multiple eyewitnesses
- Possible video evidence
- Flight crew statements
Mattler allegedly admitted that he had touched the woman.
According to investigators, he allegedly told officers that he “did not think it was such a big deal.”
Authorities also say he admitted he touched “whatever he could reach” from across the armrest.
Federal Case Now Moving Forward
Mattler now faces federal criminal charges in the United States.
As the case moves through court, investigators continue reviewing witness statements, airline records, and possible surveillance evidence.
The incident has sparked renewed discussions about passenger safety, sexual misconduct during air travel, and the importance of witnesses speaking up when they see suspicious behavior.
