Picture: Dado Ruvic

Frankfurt – A state-owned German bank on Friday admitted a major financial faux pas after it confirmed it had mistakenly transferred 5 billion to four different banks on February 20.

The mistake was immediately detected and rectified, and the money recalled, Frankfurt-based lender KfW confirmed on Friday.

The bank said the problem arose from the "human error" of an experienced KfW programmer, whose input error caused payment transfer software to automatically make multiple payments to the four banks.

The bank says it regrets the incident and has "launched a comprehensive internal and external investigation so that the causes can be explained in detail."

It's not the first time KfW has been left red-faced. In 2008, in the middle of the financial crisis, the bank attracted derision after transferring 320 million euros to Lehman Brothers on the day the US investment bank filed for bankruptcy.