Two teenage boys from north-west London, and a third 19-year-old man, who were stopped in Turkey on their way to Syria are being held at a central London police station on suspicion of terrorism offences.
Scotland Yard confirmed the teenagers had returned to the UK today.
A Met police spokesman said: "Officers alerted the Turkish authorities who were able to intercept all three males, preventing travel to Syria.
"On Saturday, March 14 the three males returned to the UK and at approximately 11.10pm were arrested on suspicion of preparation of terrorist acts contrary to section five of the Terrorism Act 2006."
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