Secretary of State Rex Tillerson said the United States holds North Korea accountable for Otto Warmbier's "unjust imprisonment"
"We hold North Korea accountable for Otto Warmbier’s unjust imprisonment, and demand the release of three other Americans who have been illegally detained," Tillerson said in the statement.
Otto Warmbier, 22, was released from North Korea and handed over to the US authorities last week, but he passed away on Monday. It later turned out that the young man was in a coma. Doctors said the released detainee suffered a severe brain damage, TASS news agency reported.
Warmbier arrived in North Korea from Beijing as a tourist on December 25, 2015. On the night of January 1 he entered a staff room at the hotel and pulled down a political poster from the wall. He was sentenced to 15 years in prison by North Korea’s Supreme Court. Warmbier was accused of an attempt to "undermine unity of the Korean people."