By Ginny McCabe

WYOMING, Ohio (Reuters) – Friends and family members will gather in Ohio on Thursday to say goodbye to an American student who died days after being returned to the United States in a coma following 17 months in captivity in North Korea.

Otto Warmbier, 22, was arrested in the reclusive communist country while visiting as a tourist. He was brought back to the United States last week with brain damage, in what doctors described as state of “unresponsive wakefulness,” and died on Monday.

A public memorial will be held on Thursday morning at Wyoming High School, in the Cincinnati suburb of Wyoming. Warmbier will be buried later in the day at a local cemetery.

The exact cause of his death is unclear. Officials at the University of Cincinnati Medical Center, where he was treated, declined to provide details, and Warmbier’s family on Tuesday asked that the Hamilton County Coroner not perform an autopsy.

Warmbier’s father, Fred Warmbier, told a news conference last week that his son had flourished while at the high school.

“This is the place where Otto experienced some of the best moments of his young life, and he would be pleased to know that his return to the United States would be acknowledged on these grounds,” he said.

After graduating as class salutatorian in 2013, Warmbier enrolled at the University of Virginia in Charlottesville, where he was studying at the school of commerce and was a member of the Theta Chi fraternity. Warmbier was scheduled to graduate this year.

At a memorial service on Tuesday night, students at the university remembered Warmbier as outgoing and energetic.

“Being with Otto made life all the more beautiful,” Alex Vagonis, Warmbier’s girlfriend, said.

Warmbier was traveling in North Korea with a tour group, and was arrested at Pyongyang airport as he was about to leave.

He was sentenced two months later to 15 years of hard labor for trying to steal an item bearing a propaganda slogan from his hotel, North Korea state media said.

Ria Westergaard Pedersen, 33, who was with Warmbier in North Korea, told the Danish broadcaster TV2 that he had been nervous when taking pictures of soldiers, and said she doubted North Korea’s explanation for his arrest.

“We went to buy propaganda posters together, so why in the world would he risk so much to steal a trivial poster? It makes no sense.”

(Wrting and additional reporting by Timothy Mclaughlin in Chicago and Jacob Gronholt-Pedersen in Copenhagen; Editing by Kevin Liffey)