The investigation into the attempt to steal an estimated £220m from the Sumitomo Mitsui Bank in the City of London is focusing on a hi-tech plot using members of the cleaning staff and bugging devices.
In an Mission Impossible-style scam, it was claimed last night, some cleaning staff placed hardware bugs onto the keyboard sockets at the back of the bank's computers where they could not be seen and then reattached the keyboards.
When the plot was uncovered investigators working for the bank found some of the devices still attached to the back of the computers.