Kgwete said the diplomat was arrested in neighbouring Mozambique in May on charges related to rhino horn smuggling.
At the time of arrest, he was driving a vehicle with a South African diplomatic registration.
South Africa`s News24 said the diplomat was arrested after 4.5 kilogrammes (10 pounds) of rhino horn and $99,300 (91,000 euros) in cash were found in his car. The news website added that Mozambican police released the man on $30,000 bail.
South Africa`s rhino poaching epidemic saw a record 1,215 rhino killed last year for their horns, which is used as a traditional medicine in some parts of Asia.
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