The North's state-run Korean Central News Agency said Friday that Warmbier was "treated in accordance with domestic law".
Otto Frederick Warmbier (C), a University of Virginia student who was detained in North Korea since early January, is taken to North Korea's top court in Pyongyang, North Korea, in this photo released by Kyodo March 16, 2016. North Korea released Warmbier last week for what it described as humanitarian reasons and he died Monday in a hospital in his hometown of Wyoming, a suburb of Cincinnati. He could not speak or move voluntarily when he returned, and his doctors said he suffered extensive brain damage.
The spokesman, who was not named, said that United States doctors who travelled to North Korea to carry out Warmbier's medical evacuation had recognised that he had been given medical treatment and, despite his serious medical condition, had been sent back to the U.S. alive.
Joseph Yun, the USA special representative for North Korea policy, who visited Pyongyang and brought Warmbier home.
"The smear campaign against (North Korea) staged in the US compels us to make firm determination that. we should further sharpen the blade of law", said the spokesman, adding, "The US should ponder over the consequences to be entailed from its reckless and rash act".
The Ohio hometown of the 22-year-old college student detained for almost a year and a half in North Korea before being sent home in a coma is making plans for his funeral.
South Korean President Moon Jae-in told CBS television earlier this week that it was clear North Korea bears a heavy responsibility for Warmbier's death. "I am anxious about other detainees, what they go through", he said. Through statements on KCNA, North Korea said it dealt with him according to its domestic laws and worldwide standards.More news: India face England in Women's World Cup opener
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But the reclusive country claimed it, not Warmbier, was the "biggest victim" in the case.
The spokesman said that Warmbier was provided with proper medical treatment, and questioned why he died so soon after returning to the US. Warmbier was sentenced to 15 years hard labor, but was sent home to OH on June 13 in a coma, dying days after his release, after spending 17 months in captivity.
The 22-year-old student was released from North Korea and handed over to the U.S. authorities on June 13, but he passed away in Cincinnati on June 19.
The 22-year-old American university student was arrested while visiting North Korea as a tourist, accused of stealing a propaganda poster and sentenced to 15 years in prison with hard labor.
"Every life is very important, Otto Warmbier's life is very important, (so are) all the detainees and 24 million people living under such a bad state right now", he said.
Warmbier was laid to rest in Wyoming, Ohio, on Thursday, June 22.