WASHINGTON - Sixteen former CIA and military intelligence officials on Tuesday urged President Bush to suspend top political adviser Karl Rove's security clearance following revelations that he played a role in outing CIA officer Valerie Plame. "We are asking that you immediately suspend the clearances of all White House personnel who spoke to reporters about (Plame's) affiliation with the CIA. They have mishandled classified information and no longer deserve the level of trust required to have access to this nation's secrets," the former officials, some of whom were covert operatives, wrote to Bush. Rove, who spoke to at least two journalists about the issue, hasn't been charged with wrongdoing in the case, but is believed to still be under investigation. Last month, special counsel Patrick Fitzgerald indicted Vice President Dick Cheney's chief of staff, I. Lewis "Scooter" Libby, on charges of perjury, false statements and obstruction of justice. The White House declined to comment on the letter Tuesday evening, saying it involves an ongoing legal matter. White House spokesman Scott McClellan was asked last week about Rove's security clearance. "I'm just not going to talk about an ongoing investigation," McClellan said at the time. Many of the former officials who signed the letter to Bush are frequent critics of his administration's handling of intelligence. At least three were Plame's classmates in training at the CIA. They also urged Bush to make clear that he wouldn't pardon anyone who is convicted in the outing of Plame, who apparently was targeted because her husband, retired ambassador Joseph Wilson, publicly criticized the administration's justification for going to war in Iraq. "If you take these steps you will be sending a clear message that your first priority is the nation's security, rather than your aides' well-being," they wrote.