LONDON , Aug. 16 (UPI) -- Between 20 percent and 25 percent of those arrested in the London riots had gang ties, the acting head of the Metropolitan Police said Tuesday. Acting Commissioner Tim Owen said the information came from an analysis of the backgrounds of those arrested last week , the Evening Standard said. Police have suggested the first riot , in Tottenham in North London , may have been instigated by gangs. Assistant Commissioner Lynne Owens, who testified at a parliamentary hearing on the riots, said police were able to use social networks to protect some important places in London , including Olympic Park and the swanky shopping district of Oxford Street. She said investigators monitored Twitter and the Blackberry messaging system , getting information on where trouble was likely to strike. "We were able to secure all those places and indeed there was no damage at any of them," she said. A 16-year-old boy appeared Tuesday in Croydon Youth Court, where he was charged with killing Richard Bowes, 68 , Sky News reported. Bowes , who lived in Ealing , a suburban district in West London, was taken off life support Thursday, several days after he was beaten into a coma.Related Topics Articles：

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