"We did a thorough analysis of all activity in our markets during the Flash Crash, and concluded – along with regulators – that the Flash Crash was not caused by the futures market," CME said in a statement emailed to Reuters. "If new information comes to light we look forward to reviewing it with the (Commodity Futures Trading) Commission."

CME also said it was prohibited by law from releasing any information on Navinder Singh Sarao, the British trader accused of the manipulation involving CME stock index futures contracts and now being held in a London jail.

(Reporting by Ann Saphir; Editing by Christian Plumb)