The arrest and detention of American Korean War veteran Merrill E. Newman highlights North Korea’s holding of other prisoners of war who were part of a secret Army unit running covert operations inside North Korea, according to a specialist on the conflict.

Mark Sauter, a journalist and historian who has studied the Korean conflict and Americans held there, said Newman’s special forces unit, the 8240th Army Unit, trained and armed anti-communist guerrillas that operated inside the Northeast Asian country and probably continued to do so after the ceasefire of July 1953.

Newman was detained Oct. 26 after mentioning to a North Korean guide during a visit to Pyongyang that he needed help locating members of an anti-communist partisan group he ran during the war, according to a Pyongyang government statement.

The mention of such a request likely triggered the arrest by the North Koreans who remain technically at war with South Korea and thus have made Newman the latest prisoner of war (POW) from the conflict.

"It’s a terrible irony that America’s newest Korean War POW is linked to some of best-known unreturned U.S. prisoners from the war—the so-called Ashley Five," Sauter said in an interview. "Newman has just been imprisoned. The Ashley Five were captured in 1953 and never returned."

The Ashley five that were reported alive in North Korea 60 years ago include Lt. Gilbert Ashley; Airman Hidemaro Ishida; Lt. Arthur Olsen; Lt. John Shaddick; and Lt. Harold Turner. The men were taken prisoner after their B-29 bomber crash-landed south of Pyongyang during an aerial bombing mission. Guerrilla fighters later tried to free them as part of an operation called Green Dragon. It is not known if Newman took part but his unit was in charge of that operation, Sauter said.

Newman, an 85-year-old California resident, was shown on North Korean state television Friday making what appeared to be a coerced public apology.

White House Press Secretary Jay Carney said yesterday that the administration is deeply concerned about Newman and another American held by the North Koreans, Kenneth Bae, who was imprisoned in North Korea over a year ago.

"We also urge the immediate release of Merrill Newman, who was detained more recently," Carney said. "Given Mr. Newman's advanced age and health conditions, we urge the DPRK to release Mr. Newman so he may return home and reunite with his family."

According to a "letter of apology" released Saturday in North Korea, Newman confessed that he had "committed many indelible crimes against the government of the DPRK and the Korean people as an adviser with the Kuwol Unit that was attached to the United Nations Korea 6th Partisan Regiment under the Intelligence Bureau of the U.S. Far East Command."

DPRK is the acronym for Democratic People’s Republic of Korea, the official name of the communist regime.

The statement said Newman provided military and guerrilla training to 300 anti-communist fighters and helped organize 200 members of a covert group that conducted intelligence gathering on the North Korean Army.

The operations involved the deaths of about 50 soldiers, the statement said.

The statement said Newman planned to meet survivors of the Kuwol Unit and to remember those who died. He had also planned to arrange for the survivors or their families to meet South Korean members of a Kuwol veterans group.

Newman said he understands that he "cannot be forgiven" for his crimes but nevertheless issued an apology to the North Korean government and said, "I want not punish me," in his often grammatically incorrect prepared statement.

Newman’s family said in a statement made public Saturday that he is in good health, according to Swedish diplomats in Pyongyang who met with him at a hotel.

"Merrill reports that he is being well treated and that the food is good," the statement said. "Our focus now is on getting him home quickly to join his loved ones, who miss him deeply. We are asking that the DPRK authorities take into account his health and his age and, as an act of humanitarian compassion, allow him to depart immediately for home. All of us want this ordeal to end and for the 85 year-old head of our extended family to be with us once more."

Newman is a retired financial executive who lives in Palo Alto.

Sauter said the Obama administration should press for Newman’s release and a full accounting of other missing Americans held by the North Koreans.

"The Obama Administration should demand Pyongyang return all American Korean War veterans in North Korea—because there may be more than just Merrill Newman. If so, they’ve been waiting to come home for a lot longer."

Sauter said there is no doubt the Ashley Five were alive in communist hands at the end of the Korean war.

"The only issue is what happened to them," he said. "Have they all died, or could some be alive? The U.S. government needs to find out."

The covert action program sought to set up a base for U.S.-trained anti-communist fighters inside North Korea. However, the operation was compromised after North Korean agents infiltrated the operation.

Declassified documents obtained by Sauter revealed that after the armistice was signed in July 1953, the Army radioed Lt. Ashley to inform the North Koreans that all five of American captives must be released.

The men were never heard from again and are believed to have been kept in North Korea or possibly moved to Russia or China.

Families of the Ashley Five were confirmed alive as of August 1953 but information on the operations of the 8240th remain classified.

Sauter said families of the captured soldiers learned about their fate decades after the war and have been unable to get the U.S. government to find out what happened to them.

The events of the missing Americans in North Korea are outlined in Sauter’s recently published book, American Trophies: How US POWs Were Surrendered to North Korea, China, and Russia by Washington's "Cynical Attitude".