REUTERS/Toru Hanai A man walks near a logo of Deutsche Bank AG in Tokyo July 16, 2014.
- Deutsche Bank lost 12 times more than risk modeling predicted it could in one day of trading earlier this year.
- The losses which have been described as "very unusual" are still unexplained by commentators.
- The news raises questions of risk modelling and internal controls within Deutsche Bank, which has already had a troubled year.
Traders at Deutsche Bank's US unit suffered losses 12 times larger than its risk projections estimate could occur in one day.
News of the trading day, which happened earlier this year, was detailed on a May filing from the bank, Bloomberg reported.
"There's questions about what this was…. But all we know is there was this outsized day that was two, three, four times bigger than anything we've ever seen," reporter Sonali Basak, told Bloomberg TV, adding "It's very unusual."
On 19 June, the day before news of the trading losses emerged, Deutsche bank let go of five emerging market traders.
The German headquartered bank has had a challenging year with the Fed naming the US unit "troubled" in May. DB has downsized parts of their business and let go of hundreds of employees, with some top traders leaving voluntarily.
A spokesman for Deutsche Bank declined to immediately comment.