In March 2003, two C.I.A. officials surprised Kyle D. Foggo, then the chief of the agency's main European supply base, with an unusual request. They wanted his help building secret prisons to hold some of the world's most threatening terrorists. Mr. Foggo, nicknamed Dusty, ... agreed to the assignment. With that, Mr. Foggo went on to oversee construction of three detention centers, each built to house about a half-dozen detainees. The existence of the network of prisons to detain and interrogate [captives] has long been known, but details about them have been a closely guarded secret. In recent interviews, though, several former intelligence officials have provided a fuller account. Mr. Foggo acknowledged a role, which has never been previously reported. He pleaded guilty last year to a fraud charge involving a contractor that equipped the C.I.A. jails and provided other supplies to the agency, and he is now serving a three-year sentence in a Kentucky prison. Eventually, the agency's network would encompass at least eight detention centers, including one in the Middle East, one each in Iraq and Afghanistan and a maximum-security long-term site at Guantanamo Bay, Cuba. The C.I.A. has never officially disclosed the exact number of prisoners it once held, but top officials have put the figure at fewer than 100. Mr. Foggo's success in Frankfurt, including his work on the prisons, won him a promotion back in Washington. In November 2004, he was named the C.I.A.'s executive director, in effect its day-to-day administrative chief. It was like taking a senior NCO and telling him he now runs the regiment," said A. B. Krongard, the C.I.A.'s executive director from 2001 to 2004. "It popped people's eyes."