US President Donald Trump's administration worked to secure his return.
Mr Warmbier was traveling in North Korea with a tour group, and was arrested at Pyongyang airport as he was about to leave.
Mr Warmbier was accused of trying to steal a propaganda banner while visiting North Korea in 2015 and was later convicted of subversion.
American student Otto Warmbier, center, is escorted at the Supreme Court in Pyongyang, North Korea.
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Which was fine by the Democrats who thought they were going to pounce and pick one off. "It's time for Nancy Pelosi to go, and the entire leadership team", Rice said .
"No conclusions about the cause and manner of Mr. Warmbier's death have been drawn at this time as there are additional medical records and imaging to review and people to interview", the coroner's office statement said.
"The US should ponder over the consequences to be entailed from its reckless and rash act", he said in an apparent warning over the fate of three other US citizens now being held in the country.
"The fact that Warmbier died suddenly in less than a week just after his return to the USA in his normal state of health indicators is a mystery to us as well", the agency reported.
"The smear campaign against DPRK staged in the USA compels us to make firm determination that humanitarianism and benevolence for the enemy are a taboo and we should further sharpen the blade of law", the spokesman added, referring to North Korea by its formal name, the Democratic People's Republic of Korea.
But the state-run Korean Central News Agency said Friday said that Warmbier was treated in accordance with domestic law. "But they've shown through their treatment of Otto a disregard for basic human rights for human dignity". "The US will have to reflect on the consequences of its rash deeds", the spokesperson went on to say.
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Police has arrested three more persons in connection to the case of lynching of DySP Mohammad Ayoub Pandith on Saturday. Two people suspected of involvement in the attack have been arrested, Jammu and Kashmir Director General of Police S.P.
A post-mortem examination was not carried out at the request of the family.
His parents have condemned the "awful tumultuous treatment" their son received at the hands of the North Koreans. The US authorities advise their citizens not to visit North Korea as tourists given the high risk.
Pyongyang has called Mr Trump a "psychopath". He had been in a comatose state since at least April 2016, according to two MRI scans that were on a disc that arrived with the student from North Korea, Dr. Daniel Kanter told reporters earlier in June.
The NBA Hall of Famer added he was sending "prayers and love" to Warmbier's family.
Ria Westergaard Pedersen, 33, who was with Warmbier in North Korea, told the Danish broadcaster TV2 that he had been nervous when taking pictures of soldiers, and said she doubted North Korea's explanation for his arrest.
'Bothersome' that Mueller is 'very good friends' with Comey
Trump, in the Fox News Channel interview, did not say exactly what he thought had changed about Comey's story. Senate, versus 22 percent who are more likely to believe what Trump has said, NBC News reported.
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