A man in his 80s from Berkshire is being interviewed by officers working on Operation Yewtree - the post Jimmy Savile investigation.
The man attended a south London police station by appointment at midday today.
The Metropolitan Police say he is being interviewed under caution by officers working on Operation Yewtree under the strand of the investigation termed 'Others'.
Officers executed a search warrant at an address in Berkshire on Saturday.
Operation Yewtree is a police investigation into alleged child sexual exploitation by the late Jimmy Savile and others, which started in October.
Police have refused to release any further details.
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