Arlington Must Once Again Bury Unknown Soldiers As mass grave is investigated, at least 4 sets of remains unidentifiable By Evann Gastaldo, Newser Staff Posted Mar 7, 2011 7:17 AM CST 5 comments Comments Snow covers headstones at Arlington National Cemetery in Arlington, Virginia, on January 27, 2011. (Getty Images) (Newser) – Thanks to advances in DNA science, many thought that the “unknown soldier” was a thing of the past, but now Arlington National Cemetery finds itself, once again, with multiple unknowns to bury. Of the eight sets of remains found in a single grave in October, only three have been identified while four were found to be unidentifiable. Investigators are still trying to determine the identity of the final set, which was found along with a letter and photo of a cheerleader, the Washington Post reports. Despite the setback, the new director of the Army Cemeteries Program says progress is being made at Arlington since a report revealed hundreds or even thousands of unmarked or mismarked graves, among other problems. The cemetery hired more staff, bought better equipment, and put new procedures in place, but even so, officials will probably find it impossible to account for every single grave, the director says. As for the four unknown soldiers found in the mass grave, one has already been reburied, but the other three are being held at the cemetery while the Army completes a criminal probe.