Diana's husband Adam told ITV London that the public need to stand up and say "this isn't good enough."
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Some 26 schoolchildren who went missing in the Brecon Beacons during a Duke of Edinburgh exercise have all been found safe and well.
Charaf Elmoudden went to the singer's four-bedroom house in north-west London last year and made off with goods worth more than £200,000.
The plea has been postponed in case where man is accused of dismembering a police officer he met on gay dating website Grindr.