Pyongyang, North Korea (CNN)American college student Otto Warmbier has landed back in the United States after more than 17 months in detention in North Korea.

[restrict]

Warmbier has been in a coma for over a year, according to his parents, and will be rushed to the University of Cincinnati Medical Center late Tuesday, a hospital spokeswoman said.

His return to the US comes as questions swirl about his health and what happened to him while he was detained by the North Korean government. The 22-year-old contracted botulism last year and is in “bad shape,” a source close to the family told CNN. North Korea told a US official that Warmbier contracted botulism and slipped into the coma after taking a sleeping pill, a senior State Department official told CNN.

“Otto has left North Korea. He is on Medivac flight on his way home. Sadly, he is in a coma and we have been told he has been in that condition since March of 2016. We learned of this only one week ago,” said Fred and Cindy Warmbier in a statement.

“We want the world to know how we and our son have been brutalized and terrorized by the pariah regime in North Korean. We are so grateful that he will finally be with people who love him.”

Warmbier was detained in January 2016 at the airport in Pyongyang while on his way home. His parents say the University of Virginia student had been on a tour of the reclusive country.

North Korean authorities said they had security footage of him trying to steal a banner containing a political slogan that was hanging from the walls of his Pyongyang hotel.

That was used as evidence in his hour-long trial, during which North Korea accused him of committing “hostile acts” against the regime at the urging of a purported member of a church in his home state of Ohio, a secretive university organization and the CIA.

Warmbier was found guilty and sentenced in March 2016 to 15 years hard labor. It was the last time he was seen publicly.

North Korea: Warmbier contracted botulism

Warmbier was one of four Americans detained in North Korea.

Since last March, the US had been pressing North Korea to let Swedish officials see the four Americans, the senior State Department official told CNN. When the Swedes finally got the okay to visit, the North Koreans immediately asked for a meeting with Joe Yun, the US envoy in New York, when he was told about Otto Warmbier’s condition. [/restrict]