Counter terrorism officers have arrested a British woman at Luton Airport after she landed back in the UK from Turkey.
The Metropolitan Police's Counter Terrorism Command detained the 21-year-old, from east London, after she alighted a flight from Istanbul at 11.15am.
She was detained by Turkish authorities on Tuesday (17 March) at a bus station in Turkish capital Ankara where she was interrogated before being sent to Istanbul and deported to the UK.
She is suspected of preparing to commit acts of terrorism and was arrested under under Schedule 5 of the Terrorism Act.
Turkey is a gateway into war-torn neighbour Syria, where terror group Islamic State (Isis) control vast swathes of the nation.
On Monday (16 March), three London teenagers were arrested in Turkey for allegedly plotting to travel to Syria and join Isis.
The suspects - two 17-year-old boys and one 19-year-old man, all from north-west London - were arrested on suspicion of preparation of terrorist acts by officers from the Metropolitan Police and were released on bail from a police station in the capital.
Efforts have been made to tighten security on the Turkey/Syria border to stop would-be fighters from joining the Jihadist network.
The move followed the high profile case of Bethnal Green Academy schoolgirls Kadiza Sultana, Shamima Begum and Amira Abase, who fled to Turkey to cross into Syria to purportedly start lives as brides of Isis soldiers.