North Korean officials told United States envoys that Mr Warmbier contracted botulism after his trial and lapsed into a coma after taking a sleeping pill.
In the face of global condemnation, North Korea has conducted 10 missile tests this year.
Just two days earlier, Trump had condemned the "brutality of the North Korean regime" after the death of Otto Warmbier, an American student who was detained in North Korea for almost a year and a half.
Hundreds of mourners celebrated the life of an American college student who was detained in North Korea for over a year and died shortly after being returned home to OH in a coma.
The US student was arrested in Pyongyang past year accused of stealing a propaganda poster. Warmbier died on Monday after being returned to the United States in a coma.
Officials at the University of Cincinnati Medical Centre, where he was treated, declined to provide details, and his family asked the Hamilton County coroner not to perform an autopsy.
"I had to come out to support the family, and also just to show, in my opinion, the North Korean Government that we are a dignified country, unlike them", Mr Koss, a 70-year-old Wyoming resident, said.
Warmbier's death has considerably strained tensions between Washington and Pyongyang, which have always been at loggerheads over North Korea's nuclear missile program and the installation of a controversial American missile defense system in South Korea.
North Korea reportedly told a US official that Otto contracted botulism and slipped intothe coma after taking a sleeping pill.
It was his life that held mourners' attention Thursday as they fondly remembered a spirited student-athlete who was socially magnetic and had a positive impact on the people around him, whether it was in class, at a swim club or in his travels.
Beerck described Warmbier as a "goofy kid" who would "drop anything to help his friends". "He was a goofy kid".
The service, which lasted a little less than an hour, concluded with Warmbier's casket being carried out as a bag-piper played the spiritual Going Home.
"He had a deep desire to know God in a personal way", Thomas said. "He did things because he wanted to do them". "This is the end of one great show, but just the beginning to hundreds of new spinoffs".
Cynthia Meis, his college admissions counselor from high school, said she admires the strength displayed by Warmbier's parents in the face of such loss and the glare of global media attention. Tillerson said last week that the U.S. expected Beijing to take action against its list of 10 bodies in China that it suspected were doing illicit business with Pyongyang.