Otto Warmbier, U.S. tourist recently released from North Korean prison, has died

Otto Warmbier, an American college student who was released by North Korea in a coma last week after more than a year in captivity, died Monday, his family said.

The 22-year-old "has completed his journey home," 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 his condition as a state of "unresponsive wakefulness" and said he suffered a "severe neurological injury" of unknown cause.

'He was home'

His father, Fred Warmbier, said last week that he believed Otto had been fighting for months to stay alive to return to his family. Their statement Monday said he had looked uncomfortable and anguished after returning June 13, but his countenance later changed.

"He was peace. He was home, and we believe he could sense that," they said.

• Otto Warmbier, released to U.S. from North Korea, non-responsive to speech

Warmbier was convicted of subversion after he tearfully confessed that he had tried to steal a propaganda banner while visiting with a tour group.

'The worst mistake of my life!'

Warmbierwas 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 be reunited with his parents and two younger siblings.

He was sentenced to 15 years in prison with hard labour in North Korea.

The University of Virginia student was held for more than 17 months. His family said last week they were told he had been in a coma since soon after his March 2016 sentencing.

Doctors said he had suffered extensive loss of brain tissue and "profound weakness and contraction" of his muscles, arms and legs. His eyes opened and blinked, but without signs of understanding verbal commands or his surroundings.

North Korea blames botulism

Unresponsive wakefulness is a new medical term for a 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 he 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.

His parents told The Associated Press in a statement the day of his release that they wanted "the world to know how we and our son have been brutalized and terrorized by the pariah regime" and expressed relief he had been returned to "finally be with people who love him."

Fred Warmbier praised his son's "performance" and President Donald Trump's administration. He was critical of former president Barack Obama's approach to his son's situation.

'At least we got him home'

In a White House statement, Trump said, "Lot of bad things happened, but at least we got him home to be with his parents." He called North Korea a "brutal regime."

The younger Warmbier grew up in the northern Cincinnati suburb of Wyoming. He was salutatorian of his 2013 class at the highly rated high school, and was on the soccer team, among other activities.

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He had planned to study in China in his third year of college and heard about Chinese travel companies offering trips to North Korea.

Young Pioneer Tours described itself as providing "budget tours to destinations your mother would rather you stayed away from." Its travel options also included Iran, Iraq and former Soviet republics.

3 Americans held in North Korea

Warmbier was in the process of leaving on Jan. 2, 2016, when he was detained at the airport.

The U.S. State Department warns against travel to North Korea. While nearly all Americans who have been there have left without incident, visitors can be suddenly seized and face lengthy incarceration for what might seem like minor infractions.

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Jeffrey Fowle, also from Ohio, was detained in 2014 when he intentionally left a Bible in a night club. Fowle was freed after six months. He said he was kept isolated most of the time but not physically abused. He and others freed from North Korea have said they were coached and coerced into giving confessions.

Three Americans remain held in North Korea. The U.S. government accuses North Korea of using detainees as political pawns. North Korea accuses Washington and South Korea of sending spies to overthrow its government.

The three American citizens still in custody in North Korea are:

• Kim Dong Chul, a businessman.
• Tony Kim, a university professor.
• Kim Hak-song, auniversity employee.

Hyeon Soo Lim, a pastor who has lived in the Toronto area for three decades after emigrating from South Korea, has been detained in North Korea since 2015. Before his detention, hehad made dozens of trips to North Korea for humanitarian aid purposes, according to his church and family.