BBC reports:
Kaspersky Lab said it had detected a computer server in January being used to co-ordinate an attack that appeared to have snatched more than 500,000 euros ($700,000; £400,000) over the course of a single week.
The firm said it believed most of the victims were based in Italy and Turkey.
It said that it had alerted the authorities to the problem.
However, it added, the criminals managed to delete any evidence that could have been used to trace them before they could be identified.
The firm declined to identify the bank involved.
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