A spokesman for Mohamed al Fayed, whose son died alongside Princess Diana in 1997, said he had no comment to make.
But it added that he will be "interested in seeing the outcome", and that he trusts the Metropolitan Police will investigate the information "with vigour".
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The 13-year-old died was found dead inside the shed last night once the fire had been put out.
Tony Blair has called for Remain voters to persuade Brexit supporters that the UK is better off in the EU.
The 29-year-old victim, Manmeet Alisher, was described as a much-loved member of Brisbane's Punjabi community.