Otto Warmbier’s parents say the 22-year-old student was “brutalized” by North Korea’s “pariah regime”.
The American student is in a coma after being freed this week by North Korea.
Otto Warmbier is now being treated at the University of Cincinnati Medical Center after the flight carrying him landed in Ohio on June 13.
He was sentenced to 15 years of hard labor for attempting to steal a propaganda sign from a hotel.
Otto Warmbier was given a sleeping pill after becoming ill after his trial in 2016 and did not wake up, North Korea said.
Former US ambassador and New Mexico governor Bill Richardson, who has previously served as special envoy to North Korea and in 2016 attempted to negotiate Otto Warmbier’s release, said the student’s family had updated him on their son’s condition.
“In no uncertain terms, North Korea must explain the causes of his coma,” Bill Richardson said.
If Otto Warmbier’s illness is the direct result of brutality in prison, there might be pressure on President Trump to take action against Kim Jong-un’s regime.
Otto Warmbier is an economics student from the University of Virginia, originally from Cincinnati, Ohio.
He was in North Korea as a tourist with Young Pioneer Tours when he was arrested on January 2, 2016.
Otto Warmbier appeared emotional at a news conference a month later, in which he tearfully confessed to trying to take the sign as a “trophy” for a US church, adding: “The aim of my task was to harm the motivation and work ethic of the Korean people.”
Foreign detainees in North Korea have previously recanted confessions, saying they were made under pressure.
After a short trial on March 16, Otto Warmbier was given a 15-year prison sentence for crimes against the state.
In a statement on June 13, Otto Warmbier’s parents said: “Sadly, he is in a coma and we have been told he has been in that condition since March 2016. We learned of this only one week ago.”
They were quoted by the Washington Post as saying they had been told Otto Warmbier had contracted botulism, a rare illness that causes paralysis, soon after his trial in March 2016.
Otto Warmbier was given a sleeping pill and had been in a coma ever since, the newspaper said.
Secretary of State Rex Tillerson made no mention of Otto Warmbier’s condition in a statement, saying only that he was on his way home to be reunited with his family and would not make any further comment, out of respect for the privacy of the family.