A 22-year-old woman was arrested at Heathrow Airport from an inbound flight from Turkey on Tuesday evening (September 19).
Officers from Metropolitan Police's Counter Terrorism Command detained the young woman at around 10.20pm at the airport.
She was arrested on suspicion of membership of a proscribed organisation, contrary to section 11 of the Terrorism Act 2000.
The 22-year-old was held under the Police and Criminal Evidence Act and taken to an east London police station.
She currently remains in police custody in the capital while enquiries continue.
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