LONDON - Police arrested a 24-year-old man at London's Heathrow Airport on Monday as part of an investigation into people traveling to Syria for "alleged terrorist activity."The man, who had arrived in the UK on a plane from Bahrain, was held "on suspicion of the commission, preparation or instigation of acts of terrorism," said the force.He was taken to a police station in south London for questioning by officers from Counter Terrorism Command, the police added in a statement.British police arrested a man and a woman at Heathrow last month as part of similar investigations into travel to Syria . A 26-year-old man was charged on October 16. The woman was released without charge.