He was visiting North Korea, one of the worlds’s most isolated and unpredictable states, as a tourist when he was pulled off an Air Koryo flight in Pyongyang minutes before it was due to depart for Beijing on October 26.

A senior Obama administration official said the Swedish embassy in Pyongyang had been “heroic” in its efforts to get to see Newman but he suggested it was ultimately a mystery why the North Koreans chose to release him.

“Who knows? We can only speculate,” said the official, who spoke on condition of anonymity.

The official added that “all efforts are now on (Kenneth) Bae,” referring to another U.S. citizen being detained by North Korea since November 2012.

Bae, a Korean American who worked as a Christian missionary, was convicted by North Korea in May of crimes against the state. He has been serving a 15-year hard-labor sentence.

U.S. Vice President Joe Biden, who is visiting South Korea, spoke with Newman after his release.

“It’s a positive thing they have done, but they have Mr. Bae, who has no reason being held in the North and should be released immediately and we are going to continue to demand his release as well,” Biden said.

Separately, a State Department spokeswoman declined comment on Newman’s well-being and treatment in North Korea, referring such questions to his family.

Asked by reporters in San Francisco how the food was during his detention, Newman replied, “healthy,” but he declined to answer other questions about his stay.

Asked if he would return to North Korea, he said: “Probably not.”

Newman served during the 1950-53 Korean War and worked with Korean anti-Communist guerrillas fighting behind the lines against the socialist North.

The Democratic People’s Republic of Korea (DPRK), as the country is officially called, has called him a war criminal.

“He masterminded espionage and subversive activities against the DPRK and in this course he was involved in killings of service personnel of the Korean People’s Army and innocent civilians,” North Korea’s official KCNA news agency has said.

KCNA said Newman was released “taking into consideration his admittance of the act committed by him on the basis of his wrong understanding, apology made by him for it, his sincere repentance of it and his advanced age and health condition”.

The United States quickly welcomed North Korea’s decision to release Newman and called on Pyongyang to pardon Bae.

In Pasadena, California, Newman’s son, Jeffrey, said his father was “in excellent spirits and eager to be reunited with his family.”

“This is a great moment for us as a family and it will be even better when we are able to see him in a few hours,” Jeffrey Newman said, reading from a prepared statement. “After Merrill comes home and has a chance to get some well-deserved rest, we will have more to say about his unusual and difficult journey.”

(Additional reporting by Ben Blanchard and Michael Martina in Beijing, and Arshad Mohammed in Washington; Writing by Dina Kyriakidou; editing by Gunna Dickson) 

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