United Flight 179 traveling from Newark to Hong Kong was diverted to Goose Bay Airport in Newfoundland, Canada due to a medical emergency onboard.
The airline says medical personnel met the aircraft at the gate and the customer was transported to a local hospital.
But the plane was unable to take off again, because of a mechanical problem with one of the doors.
United Airlines released a statement that read in part: "The airport did not have customs officers overnight so we were not able to let customers depart the aircraft. An alternative aircraft is being flown in to transport customers back to Newark. We apologize to our customers and our crew is doing everything possible to assist them during the delay."
The flight was carrying 250 passengers and 15 crew members.