Customers of 25 building societies and foreign banks with British ties are to be targeted for offshore investigations by Revenue & Customs next year. As part of its tax evasion investigation, the Revenue last year succeeded in obtaining details of secret offshore accounts from five British high street banks, in a move that along with the offer of an amnesty, uncovered £400m in unpaid taxes, costing the Exchequer just £6.5m, the Financial times reports. Five people have been identified as targets for criminal sanctions, in what will be the first prosecutions for tax evasion, arising from that initial probe. The banks chosen are thought to yield the highest number of possible tax evaders, yet Stephen Camm of PricewaterhouseCoopers said he believed the taxman would use the same approach for all the banks with UK affiliations. The Revenue said that it would implement the same legal powers as it did with the first five banks: 'The intention of the new exercise will be to provide an opportunity for account holders to inform us of their own accord, if they have unpaid tax or duties and to settle their debts in a similar way to the original offshore disclosure facility.'