American student Otto Warmbier cries while speaking to reporters in North Korea in February, 2016. Warmbier died Monday.

CINCINNATI — The family of an American college student who died days after being released from North Korea in a coma says the 22-year-old “has completed his journey home.”

Otto Warmbier died Monday, relatives said in a statement. They did not cite a specific cause of death.

“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,” his parents said.

Doctors had described Warmbier’s condition as a state of “unresponsive wakefulness” and said he suffered a “severe neurological injury” of unknown cause. He arrived in Ohio on June 13 after being held for more than 17 months.

The University of Virginia student was accused of trying to steal a propaganda banner while visiting with a tour group and was convicted of subversion. He was put before North Korean officials and journalists for a televised “confession.”

“I have made the worst mistake of my life!” he exclaimed, choking up as he begged to be allowed to reunite with his parents and two younger siblings.

He was sentenced in March 2016 to 15 years in prison with hard labor. His family said it was told he had been in a coma since soon after his sentencing.

Doctors said he suffered extensive loss of brain tissue and “profound weakness and contraction” of his muscles, arms and legs. His eyes opened and blinked but without any sign that he understood verbal commands or his surroundings.

Unresponsive wakefulness is a new medical term for persistent vegetative state. Patients in this condition who have survived a coma can open their eyes, but they do not respond to commands.

People can live in a state of unresponsive wakefulness for many years with the chances of recovery depending on the extent of the brain injury.

North Korea said Warmbier went into a coma after contracting botulism and taking a sleeping pill. Doctors in Cincinnati said they found no active sign of botulism or evidence of beatings.