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2008 Nonhyeon-dong Gosiwon Murders

On 20 October 2008, Jeong Sang-jin set fire to his room in a Nonhyeon-dong gosiwon in Seoul and attacked fleeing residents with knives, killing six people and injuring seven; he was sentenced to death in May 2009.

2008년 10월 20일 논현동 고시원 살인 사건 현장 IMG 9722
2008년 10월 20일 논현동 고시원 살인 사건 현장 IMG 9722 — Credit: 서울특별시 소방재난본부(Seoul Metropolitan Fire & Disaster Headquarters) · CC BY-SA 2.0

On the morning of 20 October 2008, a mass stabbing and arson attack occurred at a four-story gosiwon building in Nonhyeon-dong, in Seoul's Gangnam District. The building's third and fourth floors and rooftop housed low-cost single-room lodgings used mainly by students preparing for state exams and migrant workers; most of the roughly 100 residents were ethnic Korean Chinese women employed at the nearby Yeongdong traditional market.

According to police, at about 8:15 a.m., 30-year-old Jeong Sang-jin, who lived on the third floor, poured gasoline on his bed and set it alight. Dressed in black with a headlamp, balaclava, and goggles concealing his face, he emerged from the smoke-filled room armed with a sashimi knife, two fruit knives strapped to his legs, and a tear gas gun in a belt holster. He then slashed and stabbed residents who were fleeing the fire. Five people died from knife wounds Jeong inflicted, and one woman died after jumping from a fourth-floor window in an attempt to escape. Seven more people were injured, four of them seriously, either by Jeong or by the fire. Three of the dead and three of the injured were Chinese citizens. Firefighters, numbering around 100, took about 30 minutes to control the blaze.

At 9:20 a.m., Jeong was rescued by a firefighter from a storage room on the fourth floor, initially believed to be another victim. Police became suspicious of his behavior, interrogated him at the scene, and he confessed. He was arrested and taken to Gangnam Police Station, where he was charged on eleven counts including murder, attempted murder, arson resulting in death, and arson of a building.

Jeong Sang-jin was born on 27 February 1978 in Hapcheon County, South Gyeongsang Province, and moved to Seoul in 2002, where he lived at the gosiwon and worked part-time as a waiter, parking valet, and food delivery man. He had chronic financial difficulties, had been unemployed since April 2008, and his family had stopped sending him money around that time. He had attempted suicide in middle school but never received therapy, and had a criminal record for repeatedly failing to attend mandatory reserve forces training.

At trial, it was determined Jeong planned the attack after a 2007 conviction for evading military service resulted in a fine that carried a mandatory prison sentence if unpaid. He moved the attack forward when he fell behind on rent and faced eviction, fearing gosiwon staff would discover weapons he had already prepared. A psychiatric examination diagnosed him with chronic depression, and he was declared legally sane, having shown awareness of his actions and premeditation. Police stated Jeong killed indiscriminately without a specific target. Jeong was sentenced to death on 12 May 2009.

Key facts

Victims
On file
Date
2008
Location
Nonhyeon-dong, Gangnam District, Seoul, South Korea
Case status
solved

Case timeline

  1. 1978-02-27

    Jeong Sang-jin is born in Hapcheon County, South Gyeongsang Province.

  2. 2002

    Jeong moves to Seoul and begins living at the Nonhyeon-dong gosiwon.

  3. 2007

    Jeong is convicted related to avoidance of military service and fined, with a mandatory prison sentence if unpaid.

  4. 2008-04

    Jeong becomes unemployed after quitting his waiter job; family stops sending him money around this time.

  5. 2008-10-20

    Jeong sets fire to his gosiwon room and stabs fleeing residents, killing six and injuring seven.

  6. 2008-10-20

    Jeong is rescued by firefighters, identified as the attacker, confesses, and is arrested and charged on eleven counts.

  7. 2009-05-12

    Jeong Sang-jin is sentenced to death.

Best coverage

No coverage has been attached to this file yet.

People

  • Jeong Sang-jin

    CONVICTED

    Sentenced to death on 12 May 2009 for murder, attempted murder, arson resulting in death, and arson of a building.

Roles reflect public records and court outcomes at the time of writing — supporting citations are on file under Sources.

Archival records

  • 2008년 10월 20일 논현동 고시원 살인 사건 현장 IMG 9722

    archival location

    2008년 10월 20일 논현동 고시원 살인 사건 현장 IMG 9722

    Credit: 서울특별시 소방재난본부(Seoul Metropolitan Fire & Disaster Headquarters) · CC BY-SA 2.0 · Source

Places

Common questions

What happened to the victim?
On 20 October 2008, Jeong Sang-jin set fire to his room in a Nonhyeon-dong gosiwon in Seoul and attacked fleeing residents with knives, killing six people and injuring seven; he was sentenced to death in May 2009.
Where did the murders happen?
Nonhyeon-dong, Gangnam District, Seoul, South Korea.
Who was convicted?
Jeong Sang-jin (Sentenced to death on 12 May 2009 for murder, attempted murder, arson resulting in death, and arson of a building.).
What is the current status of the case?
Status: solved.

Sources

  1. ENCYCLOPEDIC2008 Nonhyeon-dong gosiwon murdersWikipedia · 2026-07-07
  2. PRESSSouth Korea: Financially Troubled Man Kills Six People In Seoul Arson And Stabbing SpreeSky News · 2026-07-07
  3. PRESSContemporaneous coverage of the Nonhyeon-dong gosiwon attackenglish.chosun.com · 2026-07-07

Record history

First published
JUL 07, 2026

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