This much is certain: on a freezing January evening, a 23-year-old student boarded a train to inner Mongolia, to spend the Chinese new year with his family. Zhao Wei never reached home. By early next morning, he was dead.
Police said he had jumped to his death from a building at a railway station halfway along the line. But an online letter signed in his parents' names offers another, chilling version of events. It alleges he was led away by railway police after a petty dispute with train staff; that his corpse was covered in unexplained injuries; that officials had "left a hundred questions unanswered" and that he was murdered.
Perhaps it was the letter's anguish that spoke to its readers. Perhaps it was Zhao's ordinariness. Perhaps it was underlying distrust of officials, fuelled by a series of death in custody scandals. Whatever the reason, it seized attention: within a few days internet users had forwarded two posts about the case more than 100,000 times on the country's most popular microblog.
But shortly afterwards the appeal disappeared from the Chinese website hosting it and the news report on the case was deleted from most sites.
This week, state news agency Xinhua issued the official verdict. A careful investigation had found conclusive evidence that Zhao got off the train at Daqing in Heilongjiang "due to his own reasons; fell off the building while he was climbing over a fence and died from severe brain injury". There had been no dispute with the train crew or passengers.
With no further details forthcoming, the findings raise more questions than they answer. Why did Zhao climb off the train at an unknown station hundreds of miles from home in the middle of the night? What was he doing on the building when he fell and why was he climbing its fence?
"So Zhao Wei committed suicide … the statement chills the heart of those who still have hope for this society," wrote one person.
Another declared his suspicion more bluntly: "They killed you because they knew that if they did, they wouldn't be held accountable."
According to the online letter, Zhao moved carriages at about 10pm, telling a fellow student that he seemed to have upset the conductor by complaining that an attendant had ridiculed him in a disagreement over a seat change.
It went on: "At around 3am, the railway police came and asked Zhao Wei to come with them.
"When this classmate next saw Zhao Wei, [his] eyes were already black and blue, and his life was gone."
Photographs purportedly of Zhao showed a young man with a blackened, swollen right eye and marks on his jaw and by his ear.
"There were three wounds inside and outside his left ear … wounds in two places on his right lower jaw … a large purple bruise on his right hip and buttock, and a wound in the middle … five wounds on his right groin, and his scrotum had swollen up to the size of a pear. There were many wounds on both hands, and his left wrist bore purplish red marks that suggested he had been handcuffed," the letter added.
It begged leaders for a full investigation, warning: "If we cannot get to the bottom of Zhao Wei's death, there is a risk the same kind of thing could happen to a Qian Wei, a Sun Wei or a Li Wei.
"Deal with the murderers, return justice to this harmonious society, and hand justice back to this simple peasant couple who raised Zhao Wei these 23 years."
The Xinhua article published this week said all Zhao's injuries resulted from his fall. It added that his family had witnessed a re-examination of his body, which had subsequently been cremated, and had no objection to the investigation's results.
The Guardian has been unable to contact his family directly, despite repeated attempts over several weeks. An Oriental Morning Post article said a relative confirmed that Zhao's parents wrote the online letter.
The Hebei University of Technology, where Zhao studied, said it "didn't know anything" about the case. The ministry of railways and the railway police did not respond to faxed requests for more information.
"From the brief glimpse we were given in China's microblogs and a single mainstream media report, it seems the Zhao Wei case epitomised many issues of concern to ordinary Chinese. Most importantly, though, I think it spoke to the desire for real answers and for real justice," said David Bandurski of the China Media Project, which has archived much of the deleted material relating to the case. He added: "This was a tragedy that might befall any Chinese family. Would this family be able to find justice against vested political interests determined to cover up the truth and avoid responsibility?
"Unfortunately, this single Xinhua release, claiming against a background of complete silence that justice has been served, suggests that the answer to that question is no."