Screening customer payments for transfers to suspected scammers has saved National Australia Bank customers around A$1.9 million over the last 18 months.David Bannatyne, executive general manager of banking and payments services at the bank, said many such payments were for a flat A$15,000, though some were as high as $25,000.He said the bank's customers were usually responding to sophisticated cold-calling activities conducted offshore. He said boilerplate scams promoted high returns, in the order of 25 per cent a year, on investment schemes that claimed to excel in the field of biotechnology and similar sectors.Bannatyne said customers were most often directing the funds to accounts with banks in Singapore, as well as in Malaysia and Hong Kong.Payment characteristics, such as the amount and the receiving bank, were often sufficient to identify a payment as one arising from a probable fraud. Bannatyne said NAB would track the payment (sometimes for days) and contact the customer, who would usually agree to the return of the funds to his or her account. One customer lost $500,000 after refusing to follow the bank's counsel on the risks of continuing with the payment.He said the bank also screened payments against scams recorded by the Australian Securities and Investments Commission at its MoneySmart consumer website.Bannatyne was speaking on a panel discussing the combating of cyber crime at the Sibos 2012 conference in Osaka yesterday.