US urges North Korea to release detainee Merrill Newman
The White House has urged the release of US citizen Merrill Newman, detained in North Korea for more than a month.
On Saturday, state media in North Korea said Mr Newman, 85, had confessed to "indelible crimes" against the state during the 1950-53 Korean War.
It published what it described as a "statement of apology" by Mr Newman.
The US also called on Pyongyang to release another American, Kenneth Bae, held since November 2012 and sentenced in May to 15 years' hard labour.
"We remain deeply concerned about the welfare of the US citizens held in custody in the DPRK [North Korea]" said National Security Council spokeswoman Caitlin Hayden.
"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," she went on.
Regarding Mr Bae, a Korean-American, she said: "We continue to urge the DPRK authorities to grant him amnesty and immediate release."
Pyongyang accused Mr Bae - described as both a tour operator and Christian missionary - of using his tourism business to plot sedition.
The official Korean Central News Agency said on Saturday that Mr Newman had ordered the deaths of North Korean soldiers and civilians in the Korean War.
Although Mr Newman did serve during the Korean War, his family says he is the victim of mistaken identity.
Pyongyang's state media have routinely publicised alleged apologies from previous US detainees, which cannot be independently verified, says the BBC's Lucy Williamson in Seoul.
Authorities have previously been accused of coercing confessions from detainees.
Some observers say Mr Newman's alleged confession could allow North Korea to release him without formal legal proceedings.
Mr Newman - a pensioner from Palo Alto, California - has been held in North Korea since being taken off a plane as he prepared to leave the country on 26 October, following a 10-day tourist visit.
In a video released by North Korean authorities, Mr Newman is shown reading his alleged apology, dated 9 November.
It claims he was an "adviser of the Kuwol Unit of the UN Korea 6th Partisan Regiment part of the Intelligence Bureau of the Far East Command" - an apparent reference to one of the special operations units acting against the North.
Mr Newman apparently confesses to trying to contact surviving soldiers during his trip as a tourist.
The statement adds: "Please forgive me."
But Mr Newman's family has said there must have been "some dreadful misunderstanding" and has appealed for his release, saying he may need medication.
Another veteran, also named Merrill Newman, was awarded a Silver Star medal for his efforts during the Korean War.
He has previously told Reuters news agency he thought it was possible there had been "a case of mistaken identity".
US troops backed South Korea in the 1950-53 Korean War, which killed at least two million people.