The victim of a suspected poisoning case at the Shanghai-based Fudan University died Tuesday, some two weeks after he drank water that was allegedly poisoned by his roommate.

Fudan University said on its official Sina Weibo account that Huang Yang, 27, a third-year graduate student from its medical school, died despite intensive treatment since being admitted to the university-affiliated Zhongshan Hospital on April 1.

Huang was initially hospitalized for vomiting and fever, and later suffered liver failure and fell into a coma. The school then reported the case to local police after the hospital failed to pin down the cause.

Local police on April 11 detected toxic chemical compounds in the water left over in the dispenser at his dormitory, which he shared with two other roommates.

The police, however, did not find any clue until Huang's schoolmate received a text message from an unidentified number reminding him of a specific chemical on April 9.

Following the message, one of Huang's roommates, surnamed Lin, was identified as the suspect on April 12.

Shanghai police confirmed Tuesday that Lin is under criminal custody as a major suspect and is being interrogated.

Police also said investigations are still underway to determine the source of the toxic compound, without mentioning its name.

However, the Oriental Morning Post reported Tuesday that the compound might be N-Nitrosodimethylamine, a toxic chemical that can cause liver damage. It is generally used for scientific research and hospitals rarely purchase it.

Huang, who was raised by a family of laid-off workers in Sichuan Province, had been financed by scholarships and income from part-time jobs during his previous eight years of studies at Fudan. He ranked first in this year's medical doctor's entrance examination and was to continue his studies.

Fang Ming, a spokesman of Fudan University, denied online speculation that Lin poisoned Huang due to being jealous of his outstanding academic performance, pointing out the two students are in different majors.

"The university will try its best to cooperate with the investigation and push for a quick and convincing result to comfort Huang's family," Fang told the Global Times.

Huang's father said after he was informed of his son's condition, he arrived in Shanghai on April 3 and met the two roommates when sleeping at the dorm that night. The father did not sense anything out of the ordinary and learned that his son had noticed a problem with the water and decided to clean the dispenser.

"I don't understand the motive. Everybody loves my son and he earned his opportunity through hard work. He was such a loving and strong kid," the father said.

Zhang Jinjian, one of Huang's friends who came to the hospital, told the Global Times that his body has been sent for autopsy. "I can't believe he's gone. We just talked about our dreams after his exam."

His friends told the Global Times that Huang, known to those close to him as Yangyang, was a smart, passionate and caring person. His high school classmates from Sichuan vowed to take care of his parents for him and called for a thorough investigation.

"He chose to study medicine for his sick parents and he deserves justice," a friend surnamed Zhou said.

The public is also questioning the role and responsibility of the university in managing hazardous chemicals, although the school claimed that the source of the substance remained unclear.

Huang's cousin posted a childhood family photo on her Weibo Tuesday to mourn her elder cousin, joined by tens of thousands of netizens grieving for the loss of a young life and demanding justice.

Huang's case also reminded the public of another unsolved case at Tsinghua University in 1994, when Zhu Ling, a student who majored in chemistry, was allegedly poisoned by her roommate using thallium. Zhu suffered a severe disability in a case that to date has not been resolved.