Shashi Kumar, in-charge of the evaluation wing of Customs, said traders exporting finished diamonds were given credits by banks.
Customs duty on the import of both crude and finished diamonds has been abolished.
However, unscrupulous traders and passengers are still smuggling in the precious stone.
Some are caught by Customs at the airport, and after due adjudication process, the ceased diamonds are auctioned in open market.
Shashi Kumar, in-charge of the evaluation wing of Customs, said traders exporting finished diamonds were given credits by banks.
After receiving remittances from abroad, the same diamonds were smuggled back to the country, enabling the traders to get loans from banks again on the same set of diamonds.
“It is a sort of havala transactions through the dummy export and smuggling of finished diamonds,” said an officer of the Air Intelligence Unit.