The Bush administration has failed to fill roughly a quarter of the top leadership posts at the Department of Homeland Security, creating a "gaping hole" in the nation's preparedness for a terrorist attack or other threat, according to a congressional report to be released today.

As of May 1, Homeland Security had 138 vacancies among its top 575 positions, with the greatest voids reported in its policy, legal and intelligence sections, as well as in immigration agencies, the Federal Emergency Management Agency and the Coast Guard. The vacant slots include presidential, senior executive and other high-level appointments, according to the report by the majority staff of the House Homeland Security Committee.