Three officials from the SA Revenue Service were offered a bribe of US$30 000 - about R390 000 - by a passenger they had apprehended at OR Tambo International Airport on Tuesday.
The officials turned it down.
In a statement on Friday, SARS said the passenger, who was travelling to Dubai, was removed from his flight before take-off for questioning after he was flagged by the tax agency's risk unit.
"On the way to the customs search area, he repeatedly offered the two customs officers 'bundles of currency' in return for allowing him to leave with his backpack. Both refused this request."
After they were joined by a customs manager in an interview room, the passenger "again offered them all bundles of currency in order to secure his release".
The entire interaction, including the searching of his bag which contained R4m, was captured on CCTV cameras.
A criminal case has been lodged with police for attempted bribery, false declaration and failure to declare. The passenger was remanded into custody.
SARS said in a second incident on the same day, two additional passengers bound for Dubai were intercepted at the same airport for being in possession of undeclared currency.
A search of one of the passengers uncovered the equivalent of more than R600 000 in US dollars and Pakistani Rupees hidden in his laptop bag. A case has been opened with police.
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