Lauren Martell claims to have witnessed an alleged incident involving Rolf Harris in the bathroom of a London music studio in the early 1990s.
The woman contacted the Metropolitan Police in November when she first heard of the investigation into Jimmy Savile.
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A growing number of rank and file officers say they support being routinely armed while on duty in the wake of terror attacks.
A report claims services could have worked more efficiently in the case of Andrew Cairns, who killed his ex-partner and her young son.
Transport for London has revoked Uber's license in the capital.