Security officers guard some of the polythene bags containing the 341.7kg of heroin worth about $21m. (AP, file)

A 21-year-old man has been arrested at Lebombo border post in Komatipoort, Mpumalanga, with heroin with an estimated street value of R3.9m, the Hawks said on Friday.

Captain Dineo Sekgotodi said he was arrested on Thursday.

He was travelling from Mozambique to South Africa before Hawks intercepted and arrested him.

Twenty-five packets of heroine were found in the panels and speakers of his Opel Corsa bakkie.

He will appear in the Komatipoort Magistrate’s Court soon.

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