In March 2016, a North Korean kangaroo court, after a one hour show trial, concluded, according to the state-run North Korean Central News Agency, that Warmbier had committed a crime "pursuant to the USA government's hostile policy toward [the North], in a bid to impair the unity of its people after entering it as a tourist".
The plane carrying Mr Warmbier is said to have touched down at Cincinnati Municipal Lunken Airport on Tuesday evening, according to a witness.
"We wish him well, but we have issued travel warnings to Americans and suggested they not travel to North Korea for their own safety", U.S. Undersecretary of State Thomas Shannon told reporters after discussing the North Korean missile threat and other issues with Japanese counterparts.
As Warmbier heads to receive care in his home state of OH, the full story of his experience, the cause of his illness, and his long-term odds of recovery are still unknown.
He was detained at the airport as he was leaving the country with a tour group in January 2016.
But a senior U.S. official told the New York Times that new intelligence reports said that Mr Warmbier had been repeatedly beaten in custody.
Suzanne DiMaggio, a director and senior fellow at the New America think tank who had been involved in unofficial talks with North Korea, said on Twitter that there was a "high probability" of communication between the Trump administration and Rodman.
Sen. Rob Portman of OH said in a statement that Tillerson had confirmed to him Warmbier's release. Shortly before sentencing, was held a press-conference at which Warmbir, not hiding tears, asked forgiveness of the North Korean people, calling the attempt to steal the poster "the most bad mistake in life".
Three other Americans remain imprisoned in North Korea. He visited Warmbier with two doctors on Monday, and demanded his release on humanitarian grounds.
His parents said that he has been in the coma for over a year. He said that over the past 18 months, Warmbier's family has "had to endure more than any family should have to bear". My goal is to go over there and try to see if I can keep bringing sports to North Korea.
The US has in the past accused North Korea of detaining its citizens to use them as pawns in negotiations over its nuclear weapons programme. The University of Virginia confirmed that the 22-year-old student is in a coma. Well, he's been released - a year after he was sentenced in a one-hour trial - but he's in a coma. He also appears to have prompted recent speculation that he might become Mr. Trump's ambassador to North Korea if diplomatic relations are ever established.
U.S and North Korean officials say Rodman had nothing to do with the release of American student Otto Warmbier, who had been serving a 15-year sentence in a North Korean prison for alleged anti-state acts.
The man was loaded into an ambulance bound for the University of Cincinnati Medical Centre, where a hospital spokeswoman said he would receive treatment. Their statement said Rodman is in the "very rare position to be able to claim long-time friendships" with both leaders. It didn't respond to USA offers to send a high-level envoy to discuss Warmbier and three other Americans held by the North. He was sentenced in March after a televised tearful public confession to trying to steal a propaganda banner.