Otto Warmbier, a native of Ohio, was finally freed after 17 months of being detained by the Pyongyang government for allegedly stealing a political banner during his visit to North Korea last year. The said material was used during the court trial where he was found guilty of committing "hostile acts" while on tour. In March 2016, the American student was sentenced to 15 years hard labor and was not seen in public since then.

No sign to support botulism claim

The University of Virginia student arrived from North Korea on Tuesday. Experts said Otto was not responsive and could not move on his own when he was admitted to the hospital right after he landed on U.S.

soil. His doctors described his current state as "unresponsive wakefulness," stating that the 22-year-old patient has shown "no signs of understanding language, responding to verbal commands, or awareness of his surroundings."

These findings support his family's claim that Otto has suffered severe brain damage while he was detained in North Korea. His parents said that they were only informed of their son's condition a week before the release. Pyongyang officials explained the American student fell into a coma after contracting botulism and taking a sleeping pill last year.

The Warmbiers, however, are not convinced with this explanation. Similarly, Otto's doctors have found no trace to prove that the patient has a history of botulism poisoning. Dr. Daniel Kanter also said they are still unknowledgeable of the treatment provided to the student for his neurological injuries.

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The doctors are also uncertain what caused the injuries.

'A brilliant, adventurous, and courageous man'

Otto's father, Fred, said North Korea has denied their son "top-notch medical care" when they decided to keep his health condition a secret for a long time. He added that they are letting the medical experts find out the real reason for Otto's brain injury.

Fred also said they had asked the previous administration to handle Otto's case but failed to get any progress. After waiting and pleading for almost two years, Trump's administration heeded their call and had brought their son back.

The father said his entire family was "brutalized and terrorized" by the pariah regime in Kim Jong Un's leadership, and lauded his son for his bravery and courage after going through a lot at the hands of North Koreans. Aside from Otto, three others Americans are still detained in the country.