Updated

Deputy Attorney General James Comey (search), a veteran of terrorism and organized crime prosecutions, said Wednesday he will leave his post this fall.

Comey, 44, has been the second in command at the Justice Department since 2003, when he was appointed by President Bush to serve with then-Attorney General John Ashcroft (search). The father of five said he will return to the private sector.

He has led the department's corporate fraud task force and spurred the creation of violent crime impact teams in 20 cities, focusing on crimes committed with guns.

Comey earlier served as U.S. attorney for the Southern District of New York (search), one of the nation's most prominent prosecutorial offices and one at the front lines of terrorism, corporate malfeasance, organized crime and the drug war.

As an assistant U.S. attorney in Virginia, Comey handled the investigation of the 1996 bombing of the Khobar Towers housing complex near Dahran, Saudi Arabia, that killed 19 U.S. military personnel.

Comey sent a letter Wednesday to Bush and Attorney General Alberto Gonzales, informing them of his decision to resign.

Gonzales thanked Comey for nearly 15 years of service, calling him "a leader in combating crime and defending America against terrorism."