Chris Denning is the 13th person to have been arrested under Operation Yewtree - the investigation sparked by the Jimmy Savile scandal.
The investigation is being run in three strands and the allegations against Denning fall into the category that does not involve Savile.
Mr Denning was part of the original DJ line-up when the BBC launched Radio One in 1967. He had previously worked as a BBC2 announcer.
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