"The fact that Warmbier died suddenly in less than a week just after his return to the U.S.in his normal state of health indicators is a mystery to us as well", a Foreign Ministry spokesman said in a statement released Friday.
The University of DE is distancing itself from comments made by an adjunct professor after she said a college student who died after being held by North Korea "got exactly what he deserved". He'd been in a coma for more than a year.
They say they didn't realize that Warmbier was essentially brain dead when he arrived back home in Ohio.
Otto Warmbier's casket is carried to the hearse followed by his family and friends after a funeral service on Thursday.
Washington has considered further "secondary sanctions" against Chinese banks and other firms doing business with North Korea, which China opposes.
The North's state-run Korean Central News Agency said Friday that Warmbier was "treated in accordance with domestic law". Officials also denied allegations that Warmbier had been tortured during his time in the prison. The report did not mention Warmbier's neurological status.
Warmbier returned to the United States on June 13 in a coma and died less than a week after his return. "Later that day, that's when we found out he was ill". However, his father has insisted that he was "brutalized and terrorized" in the North Korea.
"The smear campaign against [North Korea] 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 terrible torturous mistreatment our son experienced at the hands of the North Koreans ensured that no other outcome was possible beyond the sad one we experienced today", reads a statement issued by Warmbier's family after his death. South Korean President Moon Jae-In, who had advocated talks with the North, said Pyongyang had a "heavy responsibility" in the events leading up to the University of Virginia student's death.
It demanded that South Korea return 12 restaurant workers who defected to the South previous year.
China, North Korea's main ally and trading partner, previously bought the commodity under exemptions that allowed trade for "livelihood" purposes. At present, there are three American citizens held in North Korea.