(Karen Bleier/AFP/Getty Images)

Attorney General Eric Holder ordered two federal prosecutors tonight to open criminal investigations into a series of national security leaks to the news media.

Holder appointed Ron Machen, the U.S. attorney for the District of Colombia, and Rod Rosenstein to lead the criminal investigations into recent leaks concerning a disrupted bomb plot by al Qaeda in the Arabian Peninsula and a New York Times story about President Obama ordering cyber-attacks against Iran with the Stuxnet computer worm.

"These two highly-respected and experienced prosecutors will be directing separate investigations currently being conducted by the FBI," Holder said in a statement. "I have every confidence in their abilities to doggedly follow the facts and the evidence in the pursuit of justice, wherever it leads."

The appointment of the prosecutors comes days after the chairmen and ranking members of the Congressional Intelligence Committees and other members of Congress expressed outrage over the recent leaks. Some members were calling for Holder to appoint a special prosecutor to investigate the leaks, but Holder's move may neutralize those calls.

Last month, FBI Director Robert Mueller announced the FBI was investigating leaks about the disrupted plot by al Qaeda's Yemen affiliate to smuggle a bomb designed to be concealed in underwear onto a U.S. bound jet.

"Leaks such as this threaten ongoing operations, puts at risk the lives of sources, makes it much more difficult to recruit sources, and damages our relationships with our foreign partners." Mueller said on May 16 before the Senate Judiciary Committee.

The averted attack was first revealed by The Associated Press but, a day later, it was revealed that the individual at the center of the plot was a double agent working for Britain's MI-6 secret intelligence service and the CIA along with Saudi Arabian intelligence assets.

"Leaks such as this have … a huge impact on our ability to do our business, not just on a particular source and the threat to the particular source, but your ability to recruit sources is severely hampered," Mueller said, describing the implications of the leak of sensitive national security information.

Mueller continued, "In cases such as this, the relationship with your counterparts overseas are damaged and which means that an inhibition in the willingness of others to share information with us where they don't think that information will remain secure. So it also has some long-term effects, which is why it is so important to make certain that the persons who are responsible for the leak are brought to justice."

The other leak investigation involves recent disclosures in a June 1, 2012, New York Times article by journalist David Sanger about the Stuxnet computer virus being used to target Iran's nuclear facility. While Stuxnet has widely been discussed in the press and among computer researchers, the article contained the code name of the operation - "Olympic Games" - and included details about how the United States worked with Israel to design the computer worm.

Four days after the Times article, Sen. John McCain, R-Ariz., took to the Senate floor and implied the leaks were released by the White House for political purposes.

"A really disturbing aspect of this is that one could draw the conclusion from reading these articles that it is an attempt to further the president's political ambitions for the sake of his re-election at the expense of our national security," McCain said on the Senate floor late Tuesday.

"The notion that my White House would purposefully release classified national security information is offensive. It's wrong," the president told reporters at the White House on Friday.

The trouble for the White House may be that Sanger's article quoted an anonymous presidential aide and made several references to officials who were in the White House Situation Room.

On Wednesday, White House press secretary Jay Carney bristled that McCain had alleged the leaks were coming from the White House.

"Any suggestion that this administration has authorized intentional leaks of classified information for political gain is grossly irresponsible," Carney said.

But former federal prosecutor Peter Zeidenberg suggested Carney should take a lesson from the Bush White House on the matter.

"He may want to speak to [former President Bush spokesman] Scott McClellan before he makes any other really hard line-in-the-sand-type statements," Zeidenberg said. "Scott got up there and said similar things."

Zeidenberg served as deputy special counsel in the leak investigation over who disclosed the identity of CIA officer Valerie Plame. Vice President Cheney's chief of staff, Lewis I. "Scooter" Libby, was not prosecuted for the disclosure of the name but was convicted on charges of lying to the FBI and a grand jury, and obstructing justice.

The new investigations will once again put journalists at the center of complex national security investigations. During the Obama administration, the Justice Department has charged five individuals for allegedly leaking national security information. The Defense Department is currently prosecuting the case of Pfc. Bradley Manning in the Wikileaks investigation.

Because of First Amendment protections for journalists, the cases can be challenging to prosecute.

"They are difficult, but they are not impossible. … They are very time-consuming and there's a lot of hurdles that have to be jumped through," Zeidenberg said. "Depending how determined you are to get to the bottom of it, you can, oftentimes.

"[The reporters] are going to fight you tooth and nail but, eventually … you can actually subpoena them - but there are strict guidelines." Zeidenberg said.

Aside from the Justice Department criminal investigation into the recent leaks, the Office of the Director of National Intelligence (DNI) is also conducting a review with the DNI's general counsel to see if the leaks about the bomb plot originated in any of the 16 agencies that DNI James Clapper oversees.

According to U.S. officials and congressional staffers, Clapper and FBI Director Mueller appeared before the heads of the intelligence committees to address their concerns about the recent disclosures. During the meeting, Clapper told the committee members that he wanted to expand the use of counterintelligence polygraphs for individuals with top security clearances.