An 18-year-old man from Grangetown in Cardiff has been arrested on suspicion of terrorism offences.
South Wales Police say he has been arrested under the Section 5, Terrorism Act 2006 for assisting in the preparation of an act of terrorism.
Police said that today's arrest was not linked to any immediate threat to public safety.
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A fine end to the weekend, with sunny spells throughout the day. Moving into the start of the week, more bright spells but feeling colder.
Off to the London Marathon today? If so, send us in your pictures.