Kang Moon-sub was born in South Korea in 1974 and was just 20 years old when he became involved with the Chijon Family, a violent gang that terrorized the country from 1993 to 1994. Like most of the gang members, Kang came from a background of poverty and instability. He had little formal education and worked in low-wage construction and factory jobs prior to his descent into organized crime.

Kang was introduced to the gang by its leader, Kim Gi-hwan, who handpicked recruits based on their willingness to obey orders, harbor resentment toward the wealthy, and participate in violent activities. Kang had no prior criminal record known to the public before joining the gang. The gang operated out of a hidden facility that included prison cells, an incinerator, and a stockpile of weapons. Kang was trained in dynamite use, kidnapping methods, and execution tactics as part of the gang’s militarized strategy.

Kang Moon-sub played an active role in the Chijon Family’s reign of terror. Their first murder took place on July 18, 1993, when the gang abducted and raped a young woman named Miss Choi, who was not wealthy but was used as a “practice” victim. She was murdered by strangulation and her body discarded. Kang’s involvement in this act marked the beginning of his violent criminal career.

In August 1993, the gang executed one of their own, 18-year-old Song Bong-un, after he stole gang funds and fled. Kang participated in the recovery and execution of Song, whose body was later found buried near the group’s secret facility. This killing underscored the group’s harsh doctrine: betrayal equaled death.

The gang's third known murder involved a couple who were abducted in September 1994. Mistaken for the rich due to the car they were driving, the male victim, a 34-year-old musician, was tortured, suffocated, and dumped off a cliff inside the same car. Kang and the other members raped the surviving woman, Lee Jeong-su, and forced her into further participation in their crimes to ensure her silence.

Days later, on September 13, 1994, the gang kidnapped factory owner Mr. So and his wife, Mrs. Park. After receiving a ransom payment of 80 million won, they still murdered both victims. Lee was forced to execute them using an air gun, under threat of death herself. The gang burned the bodies in their incinerator and grilled meat to cover the smell. Members, including Kang, reportedly ate parts of the victims’ flesh.

Kang was arrested on September 19, 1994, when he drove to a rendezvous point unaware that the police were waiting. His capture followed a major breakthrough in the case which was Lee Jeong-su’s escape and testimony. After interrogation and a detailed investigation, the police confirmed Kang's role in the gang and its multiple murders.

On November 1, 1994, Kang was sentenced to death alongside five other members. He was executed by hanging on November 2, 1995, at the Seoul Detention Center.