Wang Zhijian was a Chinese national from mainland China, described by acquaintances as a volatile and controlling man. By 2008, Wang was residing in Singapore with his girlfriend, Zhang Meng, and her teenage daughter, Feng Jianyu. Wang’s relationship with Zhang was deeply troubled, marked by frequent quarrels that neighbors later recalled hearing almost weekly from their Yishun flat. Both Zhang and her flatmate, Yang Jie, were peidu mamas—a term used in Singapore for mothers who accompany their children studying abroad.

These women were part of the community of Chinese nationals living temporarily in Singapore under social visit passes, unable to work freely under local regulations. Their lives were often financially strained and socially isolated, reliant on remittances or informal work. Wang, who moved into the flat as Zhang’s live-in boyfriend, appeared to struggle with insecurity and jealousy toward the other tenants and Zhang’s independent nature.

According to witnesses and court findings, Wang exhibited possessive and erratic behavior in the days leading up to the killings. Neighbors recalled loud arguments, shouting, and sounds of objects being thrown in the week before the murders. On the night of September 18–19, 2008, this tension errupted into one of Singapore’s most shocking murder cases of the decade.

On the night of September 18, 2008, after an argument with Zhang, Wang retrieved a serrated knife from the kitchen and stabbed her multiple times in her bedroom. Her daughter, Feng Jianyu, awakened by the commotion, entered the room and was also fatally stabbed. Wang then proceeded to the room of the tenants, Yang Jie and her daughter Li Meilin. He attacked Li, inflicting severe injuries. Yang attempted to escape by climbing out of the kitchen window but was allegedly slashed on the fingers by Wang, causing her to fall six stories to her death. Wang then returned to Li, who had hidden in the kitchen toilet, and continued his assault until he believed she was dead. 

After the attacks, Wang showered, changed clothes, and prepared to flee but was apprehended by police the following day. Wang was charged with three counts of murder and one count of attempted murder. During his trial, he claimed diminished responsibility due to an adjustment disorder. The High Court initially convicted him of one count of murder and two counts of culpable homicide not amounting to murder. However, upon appeal, the Court of Appeal overturned the lesser convictions, finding that Wang had the intent to kill all three victims. He was sentenced to death and executed by hanging on May 20, 2016.