The Pentagon urged interrogators at Guantanamo Bay to destroy handwritten notes in case they were called to testify about potentially harsh treatment of detainees, a military defense lawyer said Sunday. The lawyer for Toronto-born Omar Khadr, Lt. Cmdr. William Kuebler, said the instructions were included in an operations manual shown to him by prosecutors and suggest the US deliberately thwarted evidence that could help terror suspects defend themselves at trial. Kuebler said the apparent destruction of evidence prevents him from challenging the reliability of any alleged confessions. He said he will use the document to seek a dismissal of charges against Khadr. A Pentagon spokesman, Navy Cmdr. Jeffrey Gordon, said he was reviewing the matter Sunday evening.