Police evacuated part of a terminal at Germany's busiest airport Tuesday after a security official mistakenly allowed a French family that hadn't completed required security checks into a secure area.
Federal police stopped flights from boarding and kept passengers out of area A of Frankfurt Airport's Terminal 1 for about two hours because of concerns that at least one person had entered without being properly screened.
Police tweeted that the midday evacuation was prompted by a security assistant mistakenly allowing the French family of four into the secure area even though they were supposed to be subjected to a secondary screening.
The family was located, questioned and allowed to continue on its journey, the police added.
The terminal resumed operating as normal about two hours after the partial evacuation was imposed.
Lufthansa, Germany's largest airline, said around 7,000 passengers were affected by flight delays and cancellations and that it had booked 2,000 hotel rooms as a precaution in case people couldn't be put on later aircraft.
It said also that some flights had to leave Frankfurt empty so that they would be at their destination airports at the right time to keep on schedule.
It gave no estimate of the cost to the airline.