Victim of cold case thallium poisoning dies
Zhu Ling was a college sophomore at Tsinghua University when she was poisoned with thallium in 1994.
Zhu Ling, the victim of an unsolved thallium poisoning case in 1994 which left her permanently disabled, passed away on Friday.
Tsinghua University said on its Weibo post today that Zhu Ling, its alumna from the class of 1992, passed away on December 22 in Beijing after struggling with her illness for years.
Zhu Ling was admitted to Tsinghua University in 1992.
Zhu, who majored in chemistry at the prestigious Tsinghua University, started to experience stomach pain, hair loss and other strange and debilitating symptoms in late 1994. She sunk into a coma four months later.
She was eventually diagnosed with thallium poisoning by doctors from Beijing Tongren Hospital on April 28, 1995.
Police began investigating the case in May. The main suspect was Sun Wei, Zhu's classmate and roommate at Tsinghua University, who was the only student who would have had official access to the thallium compound among the students with a close relationship to Zhu.
The public security authorities, due to a lack of conclusive evidence proving that Sun Wei was involved, announced the removal of suspicion against her in 1998.
Despite widespread awareness by the public, and police investigation into the case, the lack of eyewitnesses and physical evidence has kept the identity of the suspect in the case unresolved for several decades.
In 2013, the Beijing police issued an official response to the case, stating that the reason for the unresolved status of the case was the significant delay between Zhu showing poisoning symptoms and the police receiving the case report, which was nearly six months. By that time, criminal traces and physical evidence had been lost.
Although the police took every criminal investigation measure available at the time, direct evidence to identify the criminal suspect has still not been obtained. This case remains unsolved.
Zhu suffered from serious brain damage, loss of most of her eyesight, and ability to speak, requiring 24-hour care from her elderly parents.
Zhu was mostly paralyzed and almost blind, with severely reduced mental function.
On November 18 this year, one week before Zhu's 50-year-old birthday, she suddenly suffered from a brain tumor, subsequently experiencing symptoms of high intracranial pressure, dilated pupils, and a high fever of 39 degrees Celsius. She then became unconsciousness.
Zhu's father, Wu Chengzhi, said the family had already been mentally and emotionally ready for her death.
"We don't feel it's an absence of justice," he told Southern Metropolis Daily on Saturday. "It's normal. The hospital has made every effort to rescue her. She will be buried in Beijing."
