WYOMING, Ohio >> The father of an American college student who was imprisoned in North Korea and was returned to his home state of Ohio in a coma says the family is “adjusting to a different reality.”

Fred Warmbier told Fox News’ Tucker Carlson today that his son, Otto, was “terrorized and brutalized” during his 17-month detention and has been in a coma for more than a year.

“The day after he was sentenced, he went into a coma,” the father said in an interview scheduled to air Thursday night. He said he and his wife, Cindy, only learned of their son’s condition last week.

The 22-year-old University of Virginia student was medically evacuated from North Korea and arrived in Cincinnati late Tuesday. He was then taken by ambulance to the University of Cincinnati Medical Center. A hospital spokeswoman did not provide an update on his condition, but said his parents planned to hold a Thursday morning news conference.

Their public appearance will be at Wyoming High School, one of Ohio’s top-rated schools. Warmbier graduated from there in 2013 as class salutatorian and had played soccer.

Residents of the northern Cincinnati suburb tied blue-and-white ribbons, the school colors, to trees near the family’s home. Joy at his release was mixed with concern over his condition.

Former New Mexico Gov. Bill Richardson, a former U.S. ambassador to the United Nations, said there should be an investigation into what happened to Warmbier leading to this “tragic situation.”

Richardson, a Democrat, credited the Department of State with securing Warmbier’s return from North Korea without any preconditions but said a forceful response from the U.S. government would be required “if its determined that there was a cover-up and Otto’s condition was not disclosed and he didn’t get proper treatment.”

City councilwoman Jenni McCauley said the tight-knit community was “thrilled” to have Warmbier back.

“Even though they’re saddened by his condition, they’re just glad for the family that he is home,” McCauley said. “For any parent, this is their worst nightmare. … We’re hoping that he will be OK.”

Warmbier was serving a 15-year prison term with hard labor in North Korea after he tearfully confessed that he tried to steal a propaganda banner while visiting the country.

Such detentions in the totalitarian nation have added to tensions between Washington and Pyongyang. Three Americans remain in custody.

The U.S. government accuses North Korea of using such detainees as political pawns. North Korea accuses Washington and South Korea of sending spies to overthrow its government.

Secretary of State Rex Tillerson said Tuesday that his department was continuing “to have discussions” with North Korea about the release of the other three imprisoned American citizens.

When asked by Fox News what he would tell the families of those detained, Fred Warmbier said, “I wouldn’t know what to say to them. This is, I’ve been told, not precedented.”