Unsolved Mysteries Wiki

Real Name: Mark V. Dennis
Nicknames: No known nicknames
Location: DMZ, Vietnam
Date: July 15, 1966


Occupation: US Navy Corpsman, Petty Officer Third Class
Date of Birth: 1946
Height: 5' 9 1/2" to 6'
Weight: Unrevealed
Marital Status: Single
Characteristics: Deeply religious, wanted to become a missionary after completing military service


Details: HM3 Mark V. Dennis joined the US Navy during the Vietnam War and served as corpsman (called a "medic" in other branches of the military). Mark was deployed to Vietnam and assigned as corpsman and served as chaplain to a unit of US Marines.


Battlefield photos of the CH-46 carrying HM3 Mark V. Dennis, Operation Hastings, July 15, 1966

On July 15, 1966, during Operation Hastings on the DMZ (separating North and South Vietnam), the CH-46 "Chinook" helicopter (# EP-171) that Mark and Marines from his unit were riding in took enemy ground fire while approaching LZ Crow (landing zone). The helicopter crashed just outside the landing zone, rolled over on its side, and exploded into a ball of smoke and flames. Thirteen of the men aboard the CH-46 were killed, including Mark, though a few men managed to escape.
Several weeks later, Mark V. Dennis's remains were returned by the US Navy to his family in Ohio. The returned remains were reportedly in such bad condition that Mark's family was advised that an open coffin service would be inappropriate. In 1966, the grieving Dennis family did not doubt that the remains they received and buried belonged to Mark.


(Left) Photo of "unidentified" POW published in the November 30, 1970 issue of Newsweek Magazine. (Right) HM3 Mark V. Dennis

A few years later, Mark's older brother, Jerry Dennis, saw a photo of an "unidentified" American POW being held in North Vietnam published in the November 30, 1970 issue of Newsweek Magazine. The POW in the Newsweek photo appeared to Jerry and other Dennis family members to be the spitting image of Mark.
Unknown to the Dennis family at the time, and not mentioned in the televised December 12, 1990 “Unsolved Mysteries” episode, the "unidentified" POW in the photo that Newsweek published in 1970 had previously been identified as US Navy Lt. Paul E. Galanti by Life Magazine in its October 20, 1967 issue. (The Life Magazine cover featuring Galanti can be viewed at a link at the bottom of this article.) Galanti had been shot down and was being held prisoner of war at the infamous Hanoi Hilton in North Vietnam. An East German camera crew visited the prison and took photos of Galanti sitting in a cell. Unaware that Life Magazine had previously identified the POW as Galanti, the Dennis family naturally concluded that Mark might be alive somewhere in Vietnam. Jerry Dennis decided to personally investigate the circumstances surrounding his brother's reported death.
Another fact about the case not mentioned in the December 12, 1990 "Unsolved Mysteries" episode is that, according to the October 7, 1971 edition of the "Daily Reporter" newspaper of Dover, Ohio, shortly after Jerry Dennis began his investigation the US Navy informed the Dennis family that the POW in the Newsweek photograph is Paul E. Galanti, "...a Navy pilot Hanoi has acknowledged holding. The Dennises have now agreed the photo shows Galanti, but they still feel the body they have is not Mark's and they want the Navy to say their son is missing (Daily Reporter)."
Jerry also learned that everyone killed in the helicopter crash had been positively identified, except for Mark, whose identity was assumed by the US Navy through process of elimination.
In 1971, a veteran who served in Vietnam with Mark informed the Dennis family that Mark was not on the helicopter when it crashed. The veteran assumed that Mark became a POW in North Vietnam. Jerry Dennis then had the buried 1966 remains exhumed.
Independent forensic analysis performed at the request of the Dennis family concluded that the 1966 remains belonged to someone of about 5'7" in height. Mark was approximately 6'0" tall. The 1966 remains were also determined to be Asian, suggesting that a dead NVA enemy solider was recovered from the battlefield and misidentified as Mark. These are just a couple of examples of numerous findings from independent forensic tests on the 1966 remains that suggest that the wrong body was returned to the Dennis family for burial. A comprehensive list of forensic observations can be viewed at the Task Force Omega web site linked at the bottom of this article.
In 1981, one of the CH-46 crash survivors stated that two of the men on board had jumped out before the helicopter crashed. The US Navy did not consider this account to be credible since remains of all 13 crash victims had been officially accounted for at the crash site.
The Dennis family appealed to the Board of Correction of Naval Records to officially change HM3 Mark V. Dennis’s status from "killed in action" to "missing in action". The board ruled against changing Mark’s status. The US Navy also conducted forensic tests on the 1966 remains, consistently concluding that the body returned to the Dennis family is in fact Mark Dennis.
In December 1986, Jerry Dennis was at a bar when a man named John King overheard a conversation Jerry was having about POWs and about Mark. John King approached Jerry and said that while King was being held POW in a North Vietnam prison camp, King had known a fellow POW in the prison camp with the nickname "Preacher". Because Mark Dennis served as a chaplain to his Marine unit, Jerry believed "Preacher" may have been Mark's nickname in Vietnam. When Jerry Dennis showed John King a photograph of Mark, King said that he is positive that Mark V. Dennis is the man known as "Preacher" at the prison camp. Afterwards, Jerry Dennis lost touch with John King, but Jerry believed that the man who called himself John King had been honest about having seen Mark alive in Vietnam as a prisoner or war.
Suspects: None
Extra Notes: This case first aired on the December 12, 1990 episode.


April 4, 2017: The 1966 remains are escorted for final burial after a 2016 DNA analysis matched the remains to Mark V. Dennis

Results: Unresolved - John King has since been located after the Unsolved Mysteries broadcast and revealed to be a fraud. As reported by "Unsolved Mysteries" in a follow up on the Mark V. Dennis case, a forensic examination of the 1966 remains, involving historical x-rays of Mark V. Dennis’s spine, matched positive to spinal material from the 1966 remains. "Unsolved Mysteries" announced that it considers the case closed.
Over a period of several years, bones in the possession of the Dennis family have been tested multiple times by independent experts that concluded that the 1966 remains do not belong to Mark V. Dennis. The US Navy has continued to state that the 1966 remains belong to Mark V. Dennis.
Jerry Dennis died in 2002 without ever learning what actually happened to his brother in Vietnam.
In 2016, and after a 50-year agonizing and frustrating search for the truth, the Dennis family requested a final forensic examination of the 1966 remains, this time using advanced DNA extraction technology. The 2016 DNA test results came back from the Defense POW/MIA Accounting Agency with a positive DNA match to Mark Dennis. The Dennis family then decided to officially accept the 2016 report if only to bring some measure of closure to the case and to the long suffering of the family. The 1966 remains were then cremated and buried alongside the graves of Mark’s late mother and late father in Florida in April 2017 with full military honors.
However, in November 2014, an expedition who traveled to Vietnam and excavated the crash site discovered remains under the wreckage and positively identified through DNA as Mark Dennis. This revelation proves what the Dennis Family knew all along: that the wrong body was indeed returned to them in 1966, and that he was never a POW. The final resolution and fate of these remains has yet to be revealed.