The judicial authorities in Dendermonde (East Flanders) are trying to trace the remaining members of a gang of Nigerian fraudsters. The Nigerians were involved in an international fraud involving accounts with Citibank.
The gang first hacked the accounts of Citibank customers in Germany.
Money was then transferred from the hacked accounts to other Citibank accounts that had been opened by members of the gang here in Belgium.
The gang intended to use Belgian accounts to lauder its ill-gotten gains.
The police first became aware of the fraud two weeks ago after a tip from staff at a branch of Citibank in the East Flemish town of Aalst.
Three suspects were detained in Aalst.
Another suspected member of the gang was picked up in Antwerp when he tried to open an account at a branch of Citibank there.
The judicial authorities are working under the assumption that the fraudsters have transferred money to other Belgian accounts.
It is still not clear how much money was involved.