North Korea is reported to have detained an 85-year-old U.S. citizen and Korean War veteran who entered the country on a valid visitor's visa.
Media reports say North Korean authorities removed Merrill Newman of California from the plane on which he was about to leave the country October 26.
His son, Jeff Newman, told CNN it was his father's "life-long dream" to see the North and its culture, after serving in the South as a U.S. infantry officer in the 1950s. He said his father arranged the trip through a North Korea-approved Chinese tour company and had "all the proper visas."
Newman was traveling with a neighbor, Bob Hamrdla, who lives in the same retirement home. Hamrdla was allowed to return home. He later called the incident a "terrible misunderstanding" and expressed hope Pyongyang will release Newman for humanitarian reasons.
North Korea, which is also holding a U.S.-Korean Christian missionary on charges of subversion, has not commented on Newman's case. It is not known if he has been charged with a crime.
The top U.S. envoy to North Korea, Glyn Davies, on Thursday called on Pyongyang to resolve the issue of detained American citizens. Davies, who made his comments while in Beijing, did not mention Newman by name.
Officials at the U.S. State Department and the U.S. Embassy in Beijing say they are aware of the reports, but did not comment further.
However, the State Department on Tuesday tightened the U.S. travel warning to North Korea. The updated warning says "U.S. citizens crossing into North Korea, even accidentally, have been subject to arbitrary arrest and long-term detention."
Newman's detention comes almost a year after the arrest of another U.S. citizen, Kenneth Bae. The Korean-American missionary, detained last November 3, was convicted of state subversion and sentenced to 15 years hard labor. The 45-year-old was detained after entering North Korea as a tour operator. His family says he has diabetes and is in ill health.
It is not uncommon for North Korea to arrest foreigners on suspicion of spying or conducting illegal religious activities. The communist country's leadership views both as a threat to its hold on power.
In a separate case, North Korea said earlier this month it arrested a South Korean "spy" who was engaged in "plot-breeding" activities. On Wednesday, reports in the French news agency and South Korea's Dong-A Ilbo identified the man as 50-year-old Kim Jeong-Wook.
His family and other Christian activists told the news outlets that Kim is a missionary who was helping North Korean refugees who had escaped their homeland to China. They say Kim was arrested after traveling to Pyongyang to check on the wellbeing of several refugees who had been repatriated by Beijing.
North Korea has been accused of using foreign detainees as bargaining chips in negotiations with Western countries over its controversial nuclear weapons program.
Pyongyang has detained at least six Americans since 2009. While some were given harsh prison sentences, all were eventually released. In most cases, their release followed visits by high-ranking former or current U.S. officials.