The State Department's top investigator will examine allegations the senior U.S. diplomat in Albania tried to cover up the illegal source of ammunition a U.S. military contractor shipped to Afghanistan's military and police forces.

Tom Casey, a department spokesman, said Tuesday that the agency's inspector general has been asked "to go and look at these charges and conduct a thorough, fair and transparent investigation of these allegations."

Henry Waxman of California, who is the chairman of the House Oversight and Government Reform Committee, said Monday that John L. Withers II — the U.S. ambassador to Albania — approved a plan to remove evidence that the ammunition being supplied by AEY Inc. was made in China. AEY purchased the gear in Albania before transporting it to Afghanistan.

The State Department then attempted to conceal Withers's role from the committee, Waxman charged.

Casey called the allegations serious, but said that Withers is a career service officer who has served with distinction.