Warmbier's family said they were told by North Korean officials, through contacts with American envoys, Warmbier fell ill from botulism some time after his March 2016 trial and lapsed into a coma after taking a sleeping pill, the Washington Post reported.
A US diplomat who traveled to North Korea to secure American college student Otto Warmbier's (WORM'-birz) release also was able to make contact with three other Americans detained there. Doctors say he opens his eyes and blinks spontaneously, but that there is no indication that he understands language nor does he respond to verbal commands.
His father, Fred Warmbier, told Fox News that his son was "terrorized and brutalized" and has been in a coma for more than a year.
U.S. President Donald Trump celebrated Warmbier's return to the U.S. saying, "what's happened to him is a truly bad thing but at least the ones who love him so much can now take care of him and be with him".
Tests did not turn up evidence of botulism, which the North Koreans had claimed Warmbier contracted before being given a sleeping pill and not waking up, doctor Brandon Foreman said.
Without speculating on the cause of his injuries, Kanter and his colleagues said they found no evidence based on his condition to support the regime's explanation of botulism. Warmbier's condition apparently deteriorated shortly after he was sentenced for subversion in March 2016.
More updates on Otto Warmbier's condition should follow.
Warmbier, an American student, was imprisoned in North Korea and was apparently abused and beaten.
Richardson said he and members of his foundation had met with North Korean diplomats 20 times in the past year to try to secure the release of Warmbier and the others - Korean-Americans Tony Kim, Kim Dong Chul and Kim Hak Song and Korean-Canadian Hyeon Soo Lim.
"They lure Americans and then they take them hostage and then they do things to them and that's what happened to my son", Warmbier said, per USNews.com.
Fred Warmbier echoed the message of USA officials, who have said Rodman played no role in the release.
"He has not spoken", Kanter said.
But the young man who landed in Cincinnati and was immediately taken to a hospital isn't the same person who left a year and a half ago on a trip to explore the secretive country. The government further accused the North Korea of using him as a political pawn.
The father says that he and his wife, Cindy, only learned of their son's condition last week.
Warmbier, 22, arrived in the United States on Tuesday. The tour company also described North Korea as "probably one of the safest countries on Earth to visit". Fred Warmbier said. "I was in shock".
Asked whether he thought the previous administration could have done more, Fred Warmbier replied: "I think the results speak for themselves".
"There's no excuse for the way the North Koreans treated our son", he said.
A supporter of Mr Trump, Rodman appeared on the US Celebrity Apprentice, and earlier this week said he thought the President would be pretty happy about his visit.
A Dayton physician spoke about the type of severe brain injury sustained by college student Otto Warmbier while detained in North Korean.