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Birmingham's history of terror threats

Over the last 10 years there have been a number of terror plots and threats in Birmingham.

In the wake of the arrest of a 31-year-old man over threats to kill a police officer, special correspondent Peter Wilson assesses the impact of the latest alert.

Det Ch Insp Sue Southern, head of the West Midlands Counter Terrorism Unit, said social media had become a new battleground for would-be terrorists.