UK counter-terrorism officers dramatically stopped her plane on the runway and rescued her.
The flight, which was heading to Turkey, was turned around while officers took the teenager off the plane and returned her to her family.
The dramatic rescue of the teenager, being referred to as "terror girl" by the British media, occurred earlier this month and Scotland Yard believe their actions saved the youngster's life.
The girl
Scotland Yard would not discuss the case in detail, only that a "missing person inquiry" had been successfully resolved.
A spokesperson said: "On Saturday, December 6, police received reports of a 15-year-old girl from Tower Hamlets missing from home. Officers were able to locate her and she has since returned home safely."
It is feared more than 500 Britons have gone to Syria to fight alongside the Islamic State militants and around half have returned, posing a security risk in that country.
In a separate case, an another 15-year-old girl, whom the officers had been trying to trace, had managed to fly out of the country and is now believed to be in Syria.
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