Li Hsing‑ju (李興儒), born around 1930 in Shenyang, Liaoning Province, was a military man shaped by his time at the Republic of China Army Academy’s 23rd class. His family relocated to Sichuan during the Second Sino-Japanese War. Trained as an artillery captain, Li served in the Quemoy (Kinmen) Islands during intense cross-strait conflicts, notably the 823 Artillery Bombardment .

By 1959, he was a 29-year-old officer returned to central Taiwan. There, he met 19‑year‑old Lu Mu‑sheng, a daughter of a local family in Nantou City. The two developed a close relationship that ended when Lu became engaged to Yu Chuang Sheng, her next-door neighbour. In a painful twist, Lu introduced Li to another woman, Wu Su‑chu, encouraging a potential new relationship. This rejection came only days before Lu’s scheduled wedding—on the exact day Li would later commit the murders—intensifying his emotional turmoil.

On September 21, 1959, in Nantou City, Taiwan, Li Hsing-ju committed a mass shooting early in the morning at around 2 a.m. He had two rifles with him when he broke into the home of Lu Mu-sheng and her family. During this violent act, Li killed ten people, including Lu's father, her two brothers, and her younger sister. He also shot her 30-year-old fiancé, Yu Chuang Sheng. After shooting Lu, he seriously injured her with shots to her chest and leg.

While carrying out the shooting, Li shot at two neighbors who had come to check on the commotion. He killed one and injured the other. He then moved to a nearby apartment that belonged to another girl, whom Lu had introduced to him. In this apartment, he killed the girl's parents, her brother, and one of her sisters, while also wounding the girl and another sister.

When the police arrived and demanded that he surrender, Li turned the gun on himself and committed suicide.