WASHINGTON, Aug. 10  The two top officials of Counterintelligence Field Activity at the Defense Department resigned this week amid investigations into their agency’s classified contracts with a businessman who has pleaded guilty to bribing department officials and Representative Randy Cunningham.

The resignations, which were first reported Thursday in The Washington Post, are the latest sign that the scandal surrounding Mr. Cunningham, a California Republican who stepped down last fall, is still unfolding. The new departures come as the House intelligence committee is preparing its own report on corrupt favors performed by Mr. Cunningham as a member of the panel.

The two officials, David A. Burtt II, the director of Counterintelligence Field Activity, and Joseph Hefferon, the deputy director, could not be reached for comment. A Pentagon spokeswoman said Thursday that their resignations were “a personal decision that they both made together.”

Federal prosecutors have named the counterintelligence agency in court papers as a source of tens of millions of dollars in inflated contracts provided to Mitchell J. Wade, chief executive of the military contractor MZM Inc.