September 12, 2014 - JPMorgan says it has not seen any unusual customer fraud related to a recent cyber-attack on the bank.

The giant US bank is understood to have been the victim of a sophisticated and devastating attack on it systems after hackers exploited a zero-day vulnerability on its website. The mystery assailants managed to get past layers of security and steal gigabytes of sensitive data, according to reports.

The bank has so far been close-lipped about the incident, but in an SEC filing posted on Monday it says it has yet to see a rise in fraud levels. It reiterated that customers would not be liable for unauthorised transactions on their account so long as they 'promptly alert' the bank to any suspicious activity.

"The firm is vigilantly monitoring the situation and is continuing to investigate the matter," states the filing. "In addition, the firm is fully co-operating with government agencies in connection with their investigations."