A West Midlands Police spokeswoman said:
We can confirm that Moazzam Begg was arrested this morning.
We are confirming this name as a result of the anticipated high public interest to accredited media.
She added that naming Mr Begg does "not imply any guilt".
Head of investigations for West Midlands Counter Terrorism Unit, Detective Superintendent Shaun Edwards, said earlier:
All four arrests are connected. They were pre-planned and intelligence led. There was no immediate risk to public safety.
We continue to urge anyone planning to travel to Syria to read the advice issued by the Foreign Office.
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