A man arriving in the UK on a flight from Turkey has been arrested on suspicion of terror-related crime.
The 30-year-old was detained by the Metropolitan Police's counter-terror squad as he stepped off the plane, from Istanbul to Heathrow, on Thursday evening.
A Scotland Yard spokesman said the man had been arrested on suspicion of preparing for terrorist acts and terrorist training.
The suspect remains in custody at a south London police station, while officers search a property in the east of the capital.