British police say a man has been arrested at London's Heathrow Airport as part of an investigation into travel to Syria in support of alleged terrorist activity.

Scotland Yard said the 24-year-old, whose name and nationality were not provided, was taken into custody by counterterrorism officers after immigration officials stopped him once he arrived on a flight from Bahrain Monday morning.

Police said the man was arrested on suspicion of the "commission, preparation or instigation of acts of terrorism" and is being questioned at a south London police station.

One man previously arrested in connection with the same investigation was charged in October with the kidnapping of two Western journalists in Syria.