So says AP’s Matt Apuzzo:

"The Department’s National Security Division has recommended, and I have concluded, that there is a basis for initiating a criminal investigation of this matter, and I have taken steps to begin that investigation," Mukasey said in a statement released Wednesday.

Mukasey named John Durham, a federal prosecutor in Connecticut, to oversee the case.

Anyone know anything about John Durham?

Update: A profile on Durham here:

John H. Durham looked impatient, distracted and, odd as it might seem in the circumstance, privately amused by the spectacle of it all – which is to say, he looked pretty much like he usually looks.

He was in the cavernous new federal courthouse, off to the side of the podium, pinned down by reporters. Heavier hitters in law enforcement – drawn from their offices like moths to television lights – were looking serious and trying not to embarrass themselves while taking questions about Durham’s newest case. It involves nothing less than systemic corruption of an FBI office.

That Durham could have better explained his own case to the press is not to suggest that he is retiring. He is not. In a courtroom, prosecuting a defendant, he sometimes looks ready lunge at defense lawyers – if a 50-year-old lawyer trapped 16 hours a day in a cramped office can still lunge. He’ll clinch with anyone, anywhere. One year in Connecticut, as an assistant U.S. attorney, he put a third of New England’s mafia in jail. He has never lost a case.

[snip]

"He’s obviously a very fierce competitor," Cardinale said. "But he’s not a zealot. And he does it by the rules. He is very professional. He is courteous. I’ve been up against them all over the country and I’d put him in the top echelon of federal prosecutors. He’s such a decent guy you can’t hate him. That can make it hard to get motivated."

The view from within law enforcement is even less complicated.

"There is no more principled, there is no more better living, there is no finer person that I know of or have encountered in my life," said Richard Farley, a former assistant special agent in charge of the FBI’s New Haven division. [my emphasis]

He certainly doesn’t look like a pushover. And given that he’s taken on the FBI, he knows how to go after Federal agencies.