Imran Khan pleaded not guilty to charges of leaking state secrets under an indictment Wednesday that dealt a new blow to his chances of contesting the general election in February. Imran's lawyer contested the indictment, saying it would be valid only if signed by the accused. A guilty verdict under the Official Secrets Act could bring up to 10 years in prison. It is the second time Imran has been indicted on the same charges in the cipher case, as it is known, after a superior court struck down an earlier indictment on technical grounds.