An internal report accuses the Marine Corps of carelessly exposing tens of thousands of secret military documents to possible compromise by regularly failing to safeguard classified information.

In an unusually blunt report, Navy auditors have criticized senior Marine Corps officials in the nation's capital for "general inattention to implementing security," and their subordinates for a "less-than-diligent approach to handling classified material."The Naval Audit Service said in its Feb. 29 report that Marine Corps headquarters in Arlington, Va., has failed to keep track of most of its 60,000-plus secret documents. The whereabouts of these papers are unknown. The report also said the headquarters has sometimes discovered that secret records were missing but waited up to seven years to investigate.