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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Well what a difference a day makes! It's the calm after the storm today!
A fraudster who pretended to be in a coma for two years was caught by police going on shopping trips and holidays with his family.
After yesterday's fun and games today will feel much calmer altogether!