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The problems at Arlington National Cemetery may be more extensive than first acknowledged.
"At a conservative estimate," said Sen. Claire McCaskill, D-Mo., "4,900 to 6,600 graves may be unmarked, improperly marked or mislabeled on the cemetery's maps."
That's much higher than the estimate last month from Army investigators, who said 211 remains were affected.
"We owe our veterans better," McCaskill said. "We owe their families better."
McCaskill's comments came during a Senate hearing Thursday, where the cemetery's former superintendent and deputy superintendent testified.
John Metzler ran the cemetery for 19 years. He told the Senate committee he accepts "full responsibility" for the mix-up.
"Personally, it is very painful for me that out team at Arlington did not perform all aspects of its mission to the high standard required," he told the Senate panel.
Metzler expressed his "sincere regrets to the families," but he rebutted some of the findings of Army investigators and he suggested cemetery employees were to blame for mix-ups because the system used to track grave sites relied on a paper trial.
Metzler's former deputy Thurman Higginbotham also appeared before the panel but left the hearing early after asserting his Fifth Amendment right not to respond to questions.
Lawmakers were angry.
"The officials who let this happen," said McCaskill, "whether through ignorance, incompetence or denial, need to be held accountable."
More than 300,000 people, from war veterans to former presidents to U.S Supreme Court justices are interred there.
Arlington National Cemetery is considered among the country's most revered burial sites.
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