Wyoming, Ohio (CNN) After the bagpiper led 2,500 mourners out of the high school but before Otto Warmbier was laid to rest Thursday, one of his former counselors stopped to remember the 22-year-old who died last week after 17 months of detention in North Korea.

The tight-knit community near Cincinnati had spent nearly a year and a half "holding our breaths, praying for a quick release, rallying around the Warmbiers as much as possible" amid a dearth of information about the college student's fate, said Cynthia Meis, director of college counseling, who joined the Wyoming High School faculty in 2012.

Warmbier's alma mater was packed Thursday, as the community came to terms with its sorrow over his death -- and celebrated what Meis described as his rare combination of intelligence, affability and sincerity.

"He was going to set the world on fire, which is why this loss is so profound," she told CNN.

Fred and Cindy Warmbier, left and center, watch as the casket of their son is carried out of his funeral.

Andrew Kraner, 25, who knew Warmbier from school and swimming "up the hill at the YMCA," said the 45-minute funeral service featured a blend of serious and lighthearted moments -- which "really spoke to Otto's character." Despite the uplifting celebration of his ex-classmate's life, Kraner lamented "a very bright future that we'll never know."

"Everything they say about Otto is very true. He was the nicest kid," he said. "It's tough, and my heart's very heavy for him."

A town rallies

The funeral included a display of belongings Otto Warmbier took with him while traveling abroad.

Wyoming High's arts center can hold only 800 people, nowhere near large enough to accommodate those wishing to bid Warmbier farewell. Most attendees watched the service on monitors in overflow rooms.

Inside the arts center, mourners were met with a display of belongings Warmbier took with him on what was supposed to be a five-day excursion to North Korea. They included his wallet, running and boat shoes, a University of Virginia notebook, a scientific calculator, a reusable grocery bag and the crumpled linen blazer he wore while there.

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Among the speakers at the funeral were Warmbier's brother, Austin, his sister, Greta, and some of his friends, according to the funeral program. Also in attendance was US Ambassador Joseph Yun, the special representative for North Korea policy, who helped secure Warmbier's release.

The front of the funeral program featured a quote from Warmbier's 2013 salutatorian speech: "This is our season finale. This is the end of one great show, but just the beginning to hundreds of new spinoffs."

Following the service, funeral organizers asked supporters to line the 3-mile trek between the school and the cemetery where Warmbier was buried. On campus and around the school, ribbons of blue and white -- Wyoming High School's colors -- adorned trees to honor Warmbier.

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Parents: This is a celebration

Warmbier returned to the United States last week in a coma, only to die six days after his arrival . North Korean officials say Warmbier contracted botulism and slipped into a coma after taking a sleeping pill.

His official cause of death is unknown, as his parents declined to have an autopsy conducted on their son.

"It would be easy at a moment like this to focus on all that we lost -- future time that won't be spent with a warm, engaging, brilliant young man whose curiosity and enthusiasm for life knew no bounds," Fred and Cindy Warmbier said in a statement.

"We choose to focus on the time we were given to be with this remarkable person. You can tell from the outpouring of emotion from the communities that he touched -- Wyoming, Ohio, and the University of Virginia to name just two -- that the love for Otto went well beyond his immediate family."

Attendee D'Shon Shapiro told CNN that she and a friend, Molly Cain, know Warmbier's parents from youth sports. Otto Warmbier coached Cain's son in swimming and "made a great impression on him," she said.

Pallbearers carry Otto Warmbier's casket from Wyoming High School on Thursday.

"They truly are remarkable people, having raised remarkable kids," Shapiro said of Warmbier's parents.

Shapiro and Cain set up a fund-raiser on Facebook for the Warmbiers, with hopes of raising enough money to buy a memorial bench and to plant a tree at the young man's alma mater.

"With $10,500 raised so far, we're out of our element," Shapiro said. "What we insist on, though, is that Fred and Cindy make the decision on how to use the funds to best memorialize Otto."

Mysterious death

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Warmbier visited North Korea in January 2016 on a sightseeing tour . He was arrested for allegedly stealing a political sign from a restricted area and sentenced two months later to 15 years of hard labor.

President Donald Trump's administration worked to secure his return, and upon doing so, learned Warmbier could not speak or move voluntarily. His doctors said he suffered extensive brain damage.

His physicians said he suffered from unresponsive wakefulness , a condition also known as persistent vegetative state. In a news conference before Warmbier's death, they said they found no evidence of botulism, casting doubt on North Korea's claim.

"This pattern of brain injury is usually seen as result of cardiopulmonary arrest where blood supply to the brain is inadequate for a period of time, resulting in the death of brain tissue," Dr. Daniel Kanter said last week.

Body of Otto Warmbier loaded into hearse. People lining the 3.5 mile route to the cemetery pic.twitter.com/0TiUpGIMM9 — Miguel Marquez (@miguelmarquez) June 22, 2017

'They are responsible'

Sen. Rob Portman, R-Ohio, in remarks to reporters before the funeral, said he and his wife had spent Warmbier's 22nd birthday in December with the detained young man's parents. He described Warmbier as outgoing, athletic, bright and curious.

The senator accused North Korea of a "disregard for basic human rights, basic human dignity." He said he suspected Warmbier was denied basic medical care while detained in the reclusive country.

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"Yes, they are responsible," Portman said of the North Korean regime. "This college kid never should've been detained in the first place."

The Hamilton County Coroner's Office conducted only an external examination Warmbier's body. The coroner's office reviewed medical records from the University of Cincinnati Medical Center and the air ambulance service that helped ferry Warmbier from Pyongyang to Cincinnati.

"No conclusions about the cause and manner of Mr. Warmbier's death have been drawn at this time as there are additional medical records and imaging to review and people to interview," the coroner's office statement said.