The Central Intelligence Agency in 2004 hired outside contractors from the private security contractor Blackwater USA as part of a secret program to locate and assassinate top operatives of Al Qaeda, according to current and former government officials.

Executives from Blackwater, which has generated controversy because of its aggressive tactics in Iraq, helped the spy agency with planning, training and surveillance. The C.I.A. spent several million dollars on the program, which did not successfully capture or kill any terrorist suspects.

The fact that the C.I.A. used an outside company for the program was a major reason that Leon E. Panetta, the C.I.A.’s director, became alarmed and called an emergency meeting in June to tell Congress that the agency had withheld details of the program for seven years, the officials said.

Among the headlines promoted by publisher Thomas Dunne Books: Ridge was never invited to sit in on National Security Council meetings; was “blindsided” by the FBI in morning Oval Office meetings because the agency withheld critical information from him; found his urgings to block Michael Brown from being named head of the emergency agency blamed for the Hurricane Katrina disaster ignored; and was pushed to raise the security alert on the eve of President Bush’s re-election, something he saw as politically motivated and worth resigning over.