A video released by the Department of Defense shows the JPAC "arrival ceremony" of Vietnam and World War II vets at Joint Base Pearl Harbor-Hickam, Hawaii on December 9, 2011. The Pentagon has acknowledged that no one was actually arriving, saying the ceremonies had been "misinterpreted."

By Bill Dedman, Investigative Reporter, NBC News

Citing a report by NBC News, a senator is demanding answers from the Pentagon about the staging of arrival ceremonies for the remains of American service men and women.

Sen. Claire McCaskill (D-Mo.), who serves on the Senate Committee on Homeland Security and Governmental Affairs, wrote on Friday to Defense Secretary Chuck Hagel requesting information about any remains used in the ceremonies, and where and when they were recovered. Her letter was released this morning by the senator's office.

NBC News reported on Oct. 10 that a unit of the U.S. Department of Defense has been holding so-called "arrival ceremonies" for seven years, with an honor guard carrying flag-draped coffins off of a cargo plane as though they held the remains of missing American service men and women returning that day from old battlefields. The ceremonies are known among some military employees as "The Big Lie."

After NBC News raised questions, the Pentagon acknowledged that no honored dead were in fact arriving, and that the planes used in the ceremonies often couldn't even fly but were "static aircraft" towed into position. The Pentagon said the coffins, or transfer cases, did contain actual human remains that had "recently" arrived. The ceremonies are held by the Joint POW/MIA Accounting Command (known as JPAC), whose mission is to return and identify the 83,000 missing service men and women from World War II, Korea and Vietnam.

The head of the largest group of families of missing service men and women, Ann Mills-Griffiths, is a staunch defender of JPAC, but has previously told NBC that she has warned Pentagon officials and JPAC repeatedly that they should stop holding "those phony arrival ceremonies."

"I request that the Department provide additional information about the 'arrival' ceremonies staged by JPAC," McCaskill wrote. "This information should include the dates of all arrival ceremonies, the recovery location of remains presented at each ceremony, and the actual date the remains arrived at JPAC. I also request that you provide information about how many of the remains presented at the ceremonies have actually been identified to date. I also request that you provide any communications from the Department to the media, families, and veterans organizations regarding the ceremonies. In addition, I request that you provide any guidance or policy issued by JPAC or the Department about the ceremonies. Finally, I request that you provide a breakdown of the cost, per ceremony, including the provision of aircraft. I request that you provide this information to the Subcommittee on or before November 1, 2013 ."

American Legion: Fake ceremonies are deceptive, not symbolicThe American Legion national commander also responded to the NBC News report with a statement of his own, demanding reform by the Pentagon.

Petty Officer 1st Class Barry Hirayama / U.S. Navy A joint service honor guard escorts a transfer case during an "arrival ceremony" at Joint Base Pearl Harbor-Hickam in Honolulu on April 27, 2012. The Defense Department has acknowledged that human remains were not in fact arriving on that day. The ceremonies are held by the Pentagon's Joint POW/MIA Accounting Command.

"For families awaiting the return of their missing loved ones, The American Legion believes JPAC’s actions are deceptive and must change," said Commander Dan Dellinger. "Symbolic honors are one thing, but deception is quite another. The so-called 'Big Lie' does not honor our war dead. Instead, it misleads and insults the living. It is especially egregious during a most sensitive and vulnerable time for families. Though I am certain these deceptions were not meant to be cruel, this revelation shines a bad light on JPAC, whose mission The American Legion strongly supports, and the Pentagon. Honesty, from the beginning, would have served the Pentagon, JPAC and, most importantly, the families of our fallen heroes much more honorably.

NBC News reported in August on delays by the Pentagon in identifying the dead from previous wars, with requests for disinterments for DNA testing being denied even when a match seemed certain. Several investigations of JPAC are under way, in Congress and inside the Pentagon. An internal report called the agency "acutely dysfunctional," and a Government Accountability Office report said the effort to identify missing and unknown service men and women has been undermined by squabbling between agencies.

For more details on the arrival ceremonies, and what happens behind the scenes, see the NBC News report from Oct. 10.

YOU CAN HELP: Do you have documents or information about the Pentagon's effort to identify MIAs? Send to bill.dedman@nbcuni.com.

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