A German airline has taken legal action against a passenger for intentionally missing his flight as part of a scheme travellers use to save money on plane fares.

Key points: The passenger booked a return trip to Oslo with a stopover in Frankfurt, but did not catch his connecting flight

The passenger booked a return trip to Oslo with a stopover in Frankfurt, but did not catch his connecting flight His money-saving scheme is known as "skiplagging", where travellers book flights where their stopover city is their intended final destination

His money-saving scheme is known as "skiplagging", where travellers book flights where their stopover city is their intended final destination A travel website based around the scheme says the hack is not technically illegal, but comes with risks

The unnamed passenger had booked a return trip from Oslo to Seattle with Lufthansa, with the journey including a stopover in the German city of Frankfurt.

But on the way home he missed his flight from Frankfurt to Oslo, according to a report from CNN, opting instead to book another ticket from Frankfurt to Berlin.

The case was linked to a loophole exploited by savvy travellers.

The "hidden city" or "skiplagging" hack involves passengers booking tickets for layover journeys without intending to catch the connecting flight.

Typically, although not in this case, the layover city is the final destination for skiplaggers.

It can be a sneaky way to save money on fares, with direct flights sometimes costing more than stopover journeys.

Travellers simply restrict their luggage to carry-on and end their journey midway through the scheduled trip.

However, passengers risk complications, unexpected rerouting and threats of legal action from airlines.

In the Lufthansa case, the airline sued the man and sought 2,112 euros ($3,370) compensation for the violation of its terms.

The case was dismissed by a court in Berlin late last year, but a spokesperson told CNN an appeal had been filed.