A woman jumped out of a taxiing airplane after the flight landed at Bush Intercontinental Airport half an hour early on Monday, police say.
United Airlines flight 1892 had just arrived around 1.15pm in Houston, Texas, from New Orleans when a woman is said to have gotten out of her seat, walked to the exit and pulled the hatch on the door open, the Daily Mail reported.
She then walked out on to the wing of the plane and jumped to the ground 15 feet below.
After a moment she got up and began running toward the terminal but was caught and detained by police.
The FBI also stepped in to question her, though it was later said she was no longer in FBI custody, according to KHOU.
Passengers on the plane captured the aftermath and said the woman didn't say anything before leaping to the ground.
One passenger, Cathy Cole, wrote on Facebook about the bizarre experience.
"We landed and waited for gate to open up as we were 30 minutes early.
"A lady opened emergency exit door, which she was seated next to and jumped off plane. Ran to terminal.
"We stopped short of gate waiting and she got to the exit door open and jumped off onto the tarmac!
"Several people said "we have a runner" before we knew door was open! Jeez! Sitting in plane with sister and all passengers. Waiting for police and FAA to board.
"Now it turns out she was in (New Orleans) at United desk. Paying cash to get on this flight. She sat in isle one row in front and across from me," Cole wrote on Facebook.
Another passenger took a video on board the plane with the emergency door missing.
It is unclear if the woman is still in Houston police custody.