This photo released by North Korea's official news agency shows Merrill Newman inking his thumbprint onto a written apology for alleged crimes both as a tourist and during his participation in the Korean War. (KCNA/AFP/Getty Images)

North Korea acknowledged Saturday that it is holding an elderly U.S. citizen and said he had apologized for committing a “long list of indelible crimes” during the Korean War six decades ago. It did not indicate whether the man, Merrill E. Newman, would be released.

Newman, 85, has been held in the North for more than a month since being removed from a plane at the end of a tourist trip he had taken with a friend from his retirement community in California.

After weeks of silence, the North’s state-run Korean Central News Agency released a flurry of information Saturday on Newman’s case, including what it described as a letter from him detailing his violations in the war. It also released a video of Newman, in khakis and a green shirt, reading from the letter and marking it with an inked thumbprint.

Although there was no immediate way to gauge the letter’s authenticity, previous detainees in the North have said they were coerced into writing apologetic letters. Newman’s letter, filled with grammatical errors and perplexing run-on sentences, appeared to have been written by a nonnative English speaker.

“I realize that I cannot be forgiven for my offensives,” the letter says, “but I beg for pardon on my knees by apologizing for my offensives sincerely toward the [North Korean] government and the Korean people and I want not punish me.”

Arrested U.S. citizen in North Korea shown reading an apology on state television. (REUTERS)

A U.S. State Department spokesman said in a statement Saturday that the agency was aware of Newman’s detention but had no information about the reason. “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,” the statement said.

Newman’s family members have told the news media that the retired technology executive from Palo Alto, Calif., served in the U.S. military during the Korean War and wanted to see the North as a tourist. The friend who traveled with Newman, Bob Hamrdla, said in a statement that Newman’s detention had to stem from a “terrible misunderstanding.”

KCNA, the news agency, said in a separate article Saturday that Newman had led espionage activities against the North and was involved in the killing of military personnel and civilians.

The letter Newman is said to have written states that he served in the intelligence bureau of the United States’ Far East Command and helped spearhead attacks on communications systems, railroads and food storage areas. It also says that on his tourist trip, he had hoped to visit old war sites and connect survivors with an anti-communist group.

The letter, dated Nov. 9, sheds no light on the conditions of Newman’s detention.

Since 2009, North Korea has detained at least seven U.S. citizens, including Kenneth Bae, who has been held for more than a year. The others were released, in some cases after high-profile rescue missions, including trips by former presidents Jimmy Carter and Bill Clinton.

The United States does not maintain diplomatic relations with North Korea, a secretive police state, and depends on Swedish diplomats in Pyongyang as proxies.

Shortly after Newman’s detention, the State Department recommended that U.S citizens refrain from visiting the North.