Meanwhile, an events firm which offers people the chance to experience what it's like to take part in a riot has been accused of encouraging street violence.
People can also take on the role of police officers, in full body armour. One MP has described it as "completely wrong" and "unacceptable", especially in light of last year's disorder in Birmingham. Lee Comley reports.
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Clear tonight, with a mainly sunny day tomorrow.
Sunny and breezy on Saturday. Showery rain on Sunday.
A warm and sunny day.