The man was arrested after arriving at Gatwick Airport on a flight from Morocco
A 55-year-old man has been arrested at Gatwick Airport on suspicion of terror offences.
The suspect was held by Met counter-terrorism officers after he arrived in the UK on a flight from Morocco shortly after 11:00 BST.
He was arrested on suspicion of encouraging terrorism and dissemination of terrorist publications, police said.
The man was taken to a south London police station where he remains in custody.