Witnesses at O'Hare International Airport described the scene Thursday morning as "scary" but not panicked, as a person opened the emergency exit of a moving plane on the runway and walked out onto the wing.
"I think everybody was kind of a little surprised and kind of doing, did we really see what we saw?" said Mary Ellen Eagelston, director for NBC 7 San Diego and a passenger on the plane arriving in the Chicago area.
Eagelston took video footage of the incident while onboard, which shows the open emergency door to the plane.
"I just saw him as he was exiting out and that was it," Eagelston said. "I guess he landed on the wing and jumped down to the tarmac or slid down to the tarmac."
Dispatchers were also heard over the radio, stunned at the event.
"He jumped off of a plane?" one officer asked.
"He opened the door," dispatch said. "We got him on camera. It looks like he opened up a back door of the aircraft and walked on to the wing."
As the start of her trip to Illinois for Mother's Day, Eagelston said the flight crew handled the situation well, nothing "there was no panic."
"There was no worry," she said. "I felt like we were in good hands."
United Airlines officials confirmed that the incident occurred on flight 2874 from San Diego to Chicago.
The plane was approaching a gate when the person used the emergency exit to walk onto the wing around 4:30 a.m., Chicago police said.
The passenger then slid down the wing and onto the airfield, police said.
A recording obtained by NBC 5 of Air Traffic Control can be heard saying "We had to stop short of gave Bravo 3. Somebody pulled the rear right over wing exit. Someone in seat 21 Bravo has exited the aircraft and is on the ramp."
Cellphone video taken from the plane shows an emergency exit row of three seats with the emergency exit door opened. One passenger is seated in the middle seat and one is seated in the aisle seat.
"Our ground crew stopped the individual outside of the aircraft, and the person is now with law enforcement," United Airlines said in a statement.
"The plane then arrived at the gate and all passengers deplaned safely. The safety of our customers and crew is our highest priority.”
Officers arrived on the scene and placed the person into custody, according to police.
A person was arrested Thursday and charges were pending.
Aviation security expert Jeff Price said, though uncommon, these incidents have happened before.
"Although rare, those doors are designed to be opened and there’s really nothing to stop someone from doing it while the plane is on the ground, other than other passengers or flight attendants. Just like its hard to prevent someone from walking through a fire alarm door in a building," Price said in a statement.
The Chicago Sun-Times wire contributed to this report.
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