A man has been arrested at Heathrow Airport
Officers confirmed the suspect arrived on a plane to Heathrow before Counter Terrorism Command (SO15) detectives swooped.
Scotland Yard said the man was detained earlier this afternoon.
He is now in custody at a west London police station.
The nationality of the man is unclear.
Police in London have arrested a 36-year-old man
Police were summoned to the airport in west London last month when an Egyptian man was arrested on the tarmac.
The 50-year-old from North London was arrested as he got off a plane from Cairo at Heathrow Airport, according to police.
He was also detained on terror suspicion charges.
Police officers at Heathrow where several arrests have been made over 'terror plans'
Three suspected terrorists arrested at Heathrow Airport in three months
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In December, a 22-year-old was detained at Heathrow airport on suspicion of preparing to carry out a terror attack.
Counter-terrorism officers arrested the man when he returned to the UK from an undisclosed location on December 2.