The court heard that in several of the attacks one of the gang gained entry to the targeted shops purporting to be a customer. He then held the door open for his hammer and axe wielding accomplices who proceeded to smash the display cabinets and fill their bags with jewellery.
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The man, who was in his 30s, has not been identified, while several other people are believed to have suffered serious injuries.
If you're dreading going to work Monday morning, how about this for a career change.
Police have released more images of people wanted in connection with what they describe as 'disorder' at a McDonalds in central London.