The country's largest union, Unite, has blamed the government's defence cuts for the nearly 400 reported job losses announced at Rolls-Royce.
Unite say the scrapping of the Harrier fleet has caused redundancies at the Ansty factory, near Coventry, which it is thought will close.
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Security is being hiked up ahead of the arrival of dignitaries for the Conservative Party Conference this weekend.
Black denies claims he allegedly offered advice on how to bribe officials at other clubs.
The pair are accused of being involved in a series of gun attacks that took place last year.