More than 300,000 US military personnel are buried in Arlington Cemetery As many as 6,600 graves at the main US military cemetery were mislabeled or unmarked because of incompetence among cemetery managers, a US senator says. Senator Claire McCaskill was speaking at a US congressional hearing into contracting problems at Arlington National Cemetery. US investigators have put the problems down to poor working relationship between two top administrators. John Metzler and Thurman Higginbotham have both been called to testify. BBC