WASHINGTON — Otto Warmbier, a 22-year-old college student detained and imprisoned in North Korea for more than a year, is in a coma and has been medically evacuated from that reclusive dictatorship, his parents said Tuesday.

"Otto has left North Korea. He is on Medivac flight on his way home," Fred and Cindy Warmbier said in a statement to the Associated Press and other outlets. "Sadly, he is in a coma and we have been told he has been in that condition since March of 2016. We learned of this only one week ago."

"We want the world to know how we and our son have been brutalized and terrorized by the pariah regime in North Korea. We are so grateful that he will finally be with people who love him."

Fred Anderton, the manager at Lunken Airport, said Otto Warmbier was scheduled to land in Cincinnati Tuesday evening and be transferred via ambulance to the University of Cincinnati Medical Center.

Fred Warmbier, of Wyoming, Ohio, declined to comment to The Enquirer.

“No comment. Nothing to say… nothing to say,” he told The Enquirer Tuesday.

He said the family would hold a news conference in Cincinnati later this week, with the details yet to be finalized.

Former United Nations Ambassador Bill Richardson, who has been trying to help secure Otto’s release, said the health system in North Korean is “very primitive,” and the circumstances surrounding Otto’s condition are murky.

“This is a matter of grave concern,” Richardson told The Enquirer. “How did he fall into a coma? And why was this not disclosed?”

Phil Robertson, deputy Asia director at Human Rights Watch, said in a statement that North Korean authorities were responsible for Warmbier's fate.

"It's clear that Pyongyang has committed a grave injustice against Otto and his family, and the news that he may be returning with a serious medical problem raises concerns about what happened to him in North Korean custody," Robertson said.

At the State Department on Tuesday, spokeswoman Heather Nauert described "how pleased we are" for Warmbier to be headed home, but she declined to comment on his medical status citing the family's privacy concerns.

"What an incredible day for one of our citizens who was held in North Korea for more than a year," Nauert said. "I can’t comment anything about his health. I’m not going to characterize what their son has been through."

The Washington Post reported that Otto Warmbier is due to arrive home in Cincinnati on Tuesday evening, after being taken to an American military base in Sapporo, Japan. Nauert said she could not comment on that.

“Our son is coming home,” Fred Warmbier told The Post Tuesday morning after Otto had been evacuated from North Korea. “At the moment, we’re just treating this like he’s been in an accident. We get to see our son Otto tonight.”

Sens. Rob Portman, R-Ohio, and Sherrod Brown, D-Ohio, also applauded the news of Otto's release even as they expressed concern about the nightmarish situation Otto and his family had been put through.

"The Secretary of State has confirmed to me that Otto has been released by North Korea, and is being returned to his family,” Portman said in a statement. “Fred, Cindy, and the Warmbier family have been remarkably strong throughout this ordeal. Over the last 18 months, they have had to endure more than any family should have to bear.”

Otto’s parents, Fred and Cindy Warmbier, have been relentlessly pressing—first behind the scenes and then more publicly—for their son’s release.

“I want my kid home. He doesn’t deserve this,” Fred Warmbier told the Enquirer in an interview last month.

During his 18-month incarceration, the Warmbiers have only heard from Otto once —through a letter on March 2, 2016. He noted that the North Koreans had refused to let Swedish officials — America’s diplomatic intermediaries in that country — visit or contact Otto for more than a year.

“Since March 2nd, no one has seen or heard from Otto. No one,” Fred Warmbier said last month.

It was apparently shortly after that date when Otto Warmbier fell ill. Some media reports said the North Koreans suggested he had come down with a case of botulism and fell into a coma after being given a sleeping pill. Richardson and others questioned that account.

Tillerson's announcement came as former NBA player Dennis Rodman traveled to North Korea. Rodman, in an interview with CNN before landing in North Korea, said he was "trying to accomplish something we both need," referring to himself and the Trump administration.

More: Dennis Rodman says he's 'just trying to open a door'

Asked if he was working on the release of detained Americans, he said, "that is not my purpose right now."

Nauert, the State Department spokeswoman, said Rodman "had nothing to do with" Warmbier's release.

"We have been extremely concerned about his (Warmbier's) situation all along as we are about any American who has been detained in North Korea or anywhere in the world," Nauert said. "We strongly suggest that Americans do not go to North Korea."

Tillerson said the State Department is still working to secure the release of three other U.S. citizens detained in North Korea.

Warmbier was a University of Virginia student when he decided to go to North Korea with a tour group. He was detained when as tour group prepared to leave North Korea, charged with engaging in allegedly anti-state activity. He was sentenced in March 2016 after a televised trial in North Korea, when he publicly confessed to trying to steal a propaganda banner.

Contributing: USA TODAY reporter Oren Durell and the Associated Press.