Otto Warmbier, the American college student who was released by North Korea in a coma has died in Ohio at age 22.

His family said in a statement released by a hospital that Warmbier died Monday afternoon.

The family thanked the University of Cincinnati Medical Center for treating him but said, "Unfortunately, the awful torturous mistreatment our son received at the hands of the North Koreans ensured that no other outcome was possible beyond the sad one we experienced today."

Warmbier was sentenced to 15 years in prison with hard labor in North Korea, convicted of subversion after he tearfully confessed he had tried to steal a propaganda banner.

The University of Virginia student was held for more than 17 months and medically evacuated from North Korea last week. Doctors said he returned with severe brain damage, but it wasn't clear what caused it.