Chicago (AFP)

The father of Otto Warmbier, the US student released from North Korean detention this week, lashed out Thursday at the reclusive regime, saying he did not believe its explanation for how his son fell into a coma.

According to the hospital treating him, the 22-year-old suffered severe neurological injury during more than a year of detention in the isolated country, for stealing a political poster from a hotel.

The Warmbiers were told just a week ago that their son contracted botulism and fell into a coma shortly after being arrested and sentenced, in March last year.

"There's no excuse for the way the North Koreans treated our son and no excuse for the way they have treated so many others," Fred Warmbier told a news conference in the family's home city of Cincinnati, Ohio.

"Even if you believe their explanation of botulism and a sleeping pill causing the coma -- and we don't -- there is no excuse for any civilized nation to have kept his condition secret and denied him top-notch medical care for so long."

"I call on them to release the other Americans being held," he urged, referring to three US citizens still in North Korea.

Asked what he would say if he could speak directly to North Korean regime, Fred Warmbier replied: "I would say I'm so proud of Otto, my son, who has been in a pariah regime for the last 18 months, brutalized and terrorized, and he's now home with his family."

According to Kelly Martin, spokeswoman for the UC Health University of Cincinnati Medical Center, "Otto is in stable condition but has suffered a severe neurological injury."

The team treating him were to deliver a full medical update later in the day.

In a one-line statement earlier on Thursday on the state-run Korean Central News Agency, North Korea said it had released Warmbier "on humanitarian grounds."

- Trump call -

The university student had been on a tourist trip when he was arrested and sentenced to 15 years hard labor, a punishment the US decried as far out of proportion to his alleged crime, accusing the North of using him as a political pawn.

His release came amid tensions with Washington following a series of missile tests by Pyongyang, focusing attention on an arms buildup that Pentagon chief Jim Mattis this week dubbed "a clear and present danger to all."

Washington has stepped up pressure on China and other foreign powers to enforce existing UN sanctions on North Korea, and has deployed increased military assets of its own in the region.

Fred Warmbier expressed gratitude for the US administration's efforts in his son's favor, and said he spoke personally with President Donald Trump late Wednesday night.

"He was very candid and it was a nice conversation," he said, adding that Trump expressed concern for the family's wellbeing.

The young man's release came after a flurry of secret diplomatic contacts between Washington and Pyongyang, which culminated in Joseph Yun, the State Department's special envoy to North Korea, travelling to Pyongyang.

While there, Yun also met with the three other Americans being held, who include two men who taught at a Pyongyang university funded by overseas Christian groups, and a Korean-American pastor who was accused of espionage for the South.

Warmbier's evacuation also coincided with the arrival in Pyongyang of flamboyant retired NBA basketball star Dennis Rodman -- a former contestant on Trump's "Celebrity Apprentice" reality show.

Fred Warmbier echoed the message of US officials, who have said Rodman played no role in the release.

"Dennis Rodman had nothing to do with Otto," he said. "It's a diversion, I'm sure."

The student's father also criticized the previous administration of Barack Obama for not having done more for their son.

He said officials had counseled the family to not speak out about Otto's detention, to avoid antagonizing the reclusive regime of North Korean dictator Kim Jong-Un.

"We relied on this false premise that they would treat Otto fairly and let him go," Warmbier said. "The results speak for themselves."

Agence France-Presse

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