United Airlines put an underage passenger on a plane to the wrong country, prompting an all-night ordeal between a panicked mother and the airline to keep the plane from taking off

• A 14-year-old boy traveling as an unaccompanied minor was placed on the wrong flight Sunday night.
• He was supposed to travel to Stockholm, Sweden, but was placed on a plane heading to Düsseldorf, Germany.
• He was allowed off the aircraft, but he missed his correct flight. He was rerouted through Copenhagen, Denmark, instead.
• The boy's mother claims that the issue began when United asked her to pay extra to register her son as an unaccompanied minor, which meant that her son was escorted by United staff and placed on the wrong plane.
• United says that it does not allow travelers to register as unaccompanied minors when there's a transfer to a partner airline involved.
• Visit Business Insider's homepage for more stories.

A 14-year-old boy from Raleigh, North Carolina, flying as an unaccompanied minor endured an all-night ordeal after United Airlines directed him onto a plane heading to the wrong country.

Brenda Berg, the boy's mother, first tweeted to United just before 5:30 p.m. Sunday evening, claiming that her son was placed on the wrong plane during a transfer at Newark International Airport.

According to Berg, her son was flying from Raleigh-Durham, connecting to Stockholm in Newark. He booked his ticket on SAS, a Scandinavian airline. SAS doesn't have a direct flight between Raleigh and Stockholm, so it included a codeshare flight on United from Raleigh to Newark, where the SAS flight was scheduled to depart.

However, Berg said that her son was put on the wrong plane. It was a flight to Düsseldorf operated by the German airline Eurowings, a low-cost subsidiary of Lufthansa.

Both Eurowings and SAS operate those flights as codeshares with United.

Berg said the issue began because United forced her to register her son as an unaccompanied minor. He was not allowed to manage his own connection at Newark, and was instead brought to a room for unaccompanied minors, and led straight to the wrong plane.

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She said that when she arrived at Raleigh-Durham airport to check her son in for his flight, she was told that because he was 14, she had to pay a $150 fee for the unaccompanied-minor service. United's website says that the service is required for minors aged 5 to 14 who are traveling alone. The service provides airline representatives who assist unaccompanied minors at the airport, and during arrival.

However, United's website also states that underage passengers connecting to or from partner airlines cannot use its unaccompanied minor service.

A United spokesperson told Business Insider that a 14-year-old flying alone typically wouldn't be allowed when there's an international connection involved. However, because the ticket was sold by SAS - which only considers children 11 and under to be minors - the check-in agent decided to allow the teenager onto the connecting flight with the airport escort service.

The paperwork that the 14-year-old was given had the correct flight information on it, but there was a gate change between the time it was printed, and when he arrived at Newark for the connecting flight. A Eurowings plane, flight EW1113 to Düsseldorf, was sitting at the gate at that point.

According to the United spokesperson, the Düsseldorf flight was ready to leave, awaiting one more passenger - who had a similar name to the younger Berg. They were preparing to close the doors, calling the passenger's name, when the person escorting Berg heard the announcements, assumed it was supposed to be him, and rushed him onto the incorrect plane.

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In a phone call with Business Insider, Brenda Berg said that her son realized he had been escorted onto the wrong plane and notified a flight attendant at 4:50 p.m, while both planes were still on the ground. The Eurowings plane returned to the gate and let her son off, but the correct flight had already departed.

Berg disputed United's version of what happened, and said the correct passenger that Eurowings had been calling for as the doors were closing was already on the plane, seated next to her son.

Eventually, she tweeted that SAS helped her son book onto a later flight going to Copenhagen, Denmark, with a connection on to Stockholm.

"This is not what we wanted - an international transfer," Berg tweeted. "I have been up all night thinking about the fact that he was one call button away from landing in Germany without being on the manifest!"

Her son eventually landed in Denmark, and made the connection to Stockholm.

United issued this statement to Business Insider:

"The safety and well-being of all of our customers is our top priority, and we have been in frequent contact with the young man's family to confirm his safety and to apologize for this issue. Once Eurowings recognized that he had boarded the wrong aircraft in Newark, the plane returned to the gate - before taking off. Our staff then assisted the young customer to ensure that he boarded the correct rebooked flight later that evening. We have confirmed that this young customer safely reached his destination."

Eurowings did not immediately respond to a request for comment explaining how Berg's son was allowed to board the flight without the correct boarding pass.

United told Business Insider it had refunded the unaccompanied minor fee. Berg said she has not heard from the airline since Sunday night.

Ultimately, Berg's son made it to Stockholm, nearly 10 hours late. However, Berg worries about what would have happened under different circumstances.

"If he had been 10, this would have been so much worse! There's a lot that needs to be fixed, but ultimately, if you're going to have an unaccompanied minor program, it absolutely has to work correctly."