An effort to prosecute the self-proclaimed mastermind of the Sept. 11 terrorist attack and four co-defendants veered off track again Thursday as a pretrial hearing ended with new obstacles that threaten to further derail the case before a military tribunal at Guantanamo Bay. The prosecution had sought to start jury selection early next year, but that now seems impossible amid looming fights over classified evidence from the CIA among other issues. The prosecution of Khalid Shaikh Mohammed has already been stalled for years, initially by the U.S.