Missouri Democratic Sen. Claire McCaskill has written a letter to Army Secretary John McHugh regarding the ongoing problems at Arlington National Cemetery amid continued reports of unmarked and mislabeled graves at the national military burial ground.

In remarks on the Senate floor, McCaskill, who faces a tough re-election bid in 2012, announced that she had asked McHugh “for immediate information on an interim basis about what in fact has happened to clean up this mess at Arlington -- where they are in the process and what is the truth about graves that have been identified, have not been identified and potentially never will be identified.”

McCaskill, the chairman of the Senate Homeland Security Committee’s Ad Hoc Subcommittee on Contracting Oversight, last year co-sponsored a new law that requires congressional oversight of the burial ground.

Since the initial discovery of unmarked and mislabeled graves last year, more management problems at Arlington Cemetery have surfaced, including a report late last year of a mass grave that held the remains of eight people.

McCaskill said Thursday that she posed several questions to McHugh.

“I want to know the number of grave sites that have been physically examined to identify the remains that are there,” she said. “I want to know how many grave sites have been determined to be incorrectly identified, labeled or occupied and the methodology that’s been used to make that determination. I want to know immediately how many families have been contacted regarding problems with the grave sites and the number of families that have requested that those grave sites be physically examined.”

McCaskill added that she wanted to know the procedure for contacting those families, how the Army will be able to correctly identify all gravesites by the end of the year and “the estimated costs and time required to complete an examination of that nature.”

McCaskill said that she has asked McHugh to respond within the next week.