On the morning of September 15, 1986, the body of 71-year-old Lee Wan-im was found in a grassy field in Taean-eup, a farming township in Hwaseong County about an hour south of Seoul. She had been strangled. In a place where neighbors left doors unlocked and walked home along dark paths between rice paddies, it looked like an isolated horror. Five weeks later, on October 20, a 25-year-old woman named Park Hyun-sook was found dead near a waterway, killed the same way. Over the next five years, eight more women and girls would be bound, sexually assaulted, and strangled in the same small county — and South Korea would learn, for the first time, what a serial killer was.

A Killer in the Rice Paddies

Between September 1986 and April 1991, ten females were murdered in Hwaseong, the youngest in her early teens, the oldest 71. The killer worked at night, along footpaths, bus stops, and field edges. He bound victims with their own clothing, gagged them, and strangled several with their own stockings — a signature so consistent that detectives knew early on they were hunting one man. The last confirmed victim, a 69-year-old woman, was raped and strangled with her pantyhose on April 3, 1991. Then the killings simply stopped. Like the Monster of Florence, whose countryside attacks terrorized Italy across a similar span of years, the Hwaseong killer turned an entire rural region into a crime scene and then vanished from it, leaving police with a pattern but no name.

Two Million Officers, Twenty-One Thousand Suspects

What followed was the largest manhunt in South Korean history. Over the life of the case, police mobilized a cumulative total of more than two million officers, investigated 21,280 suspects, and compared 40,116 fingerprints, along with roughly 570 DNA samples and 180 hairs. Women were warned off the streets after dark; men whose blood type matched evidence from the scenes were pulled in by the busload. Several suspects were interrogated so brutally that their cases later became scandals of their own. The failure haunted the country for decades and inspired Bong Joon-ho’s 2003 film “Memories of Murder,” which ends with a detective staring into the camera, still searching. Like the hunt for Bible John in Glasgow, the investigation produced mountains of paper, thousands of names, and no killer.

The Eighth Murder and the Wrong Man

The eighth murder broke the pattern. In September 1988, a 13-year-old girl was raped and strangled in her own bedroom while her family was out — indoors, not on a footpath. Police decided it was a copycat crime. In July 1989 they arrested Yoon Sung-yeo, a 22-year-old machine-shop worker who lived nearby and whose arm had been withered by childhood polio. Yoon later described being kept awake for three days and beaten until he confessed. The forensic work presented against him was later found to have been manipulated. He was sentenced to life in prison, watched the real killer strike again while he sat in a cell, and was paroled in 2009 — after serving 20 years for a murder he did not commit.

A Name From a Prison DNA Database

The break finally came from a prison DNA database. In July 2019, cold-case investigators sent long-stored evidence, including a victim’s underwear, to the National Forensic Service. On September 18, 2019, police announced a match: Lee Chun-jae, a 56-year-old inmate at Busan Prison. Lee had grown up in Hwaseong and left the area in January 1994 — the same month he drugged, raped, and murdered his 18-year-old sister-in-law at his home in Cheongju. He was sentenced to death for that crime, reduced on appeal to life imprisonment, and had been quietly serving it ever since. The identification, coming barely a year after the Golden State Killer was unmasked in California, showed again that DNA does not forget, even when the law has moved on. Lee’s DNA was eventually tied to five of the Hwaseong killings.

Fourteen Murders, and No Way to Charge Them

At first Lee denied everything. Then, in early October 2019, over the course of repeated interviews, he confessed to 14 murders — all ten Hwaseong killings, including the “copycat” eighth, plus four others — and more than 30 rapes and attempted rapes. Investigators verified his account against crime-scene details only the killer could know. None of it could be prosecuted. The statute of limitations on the final Hwaseong murder had expired on April 2, 2006. South Korea abolished the limitation period for murder in 2015, prompted in part by this very case, but the change was not retroactive. On November 2, 2020, Lee appeared as a witness at Yoon’s retrial, calmly recounted his crimes in open court, and said he was surprised he had never been caught.

Apologies, an Exoneration, and a Hidden Grave

On July 2, 2020, police formally closed the investigation, and Bae Yong-ju, chief of the Gyeonggi Nambu Provincial Police Agency, bowed in apology to Yoon and to the victims’ families. The reckoning revealed fresh horrors. In December 1989, officers searching for Kim Hyun-jung — an 8-year-old girl missing since July 7, 1989 — had found her remains and belongings, concealed the discovery, and reclassified her as a runaway rather than admit another murder on their watch. Lee confessed to killing her, too. On December 17, 2020, the Suwon District Court acquitted Yoon Sung-yeo at his retrial, and the judge apologized from the bench for a justice system that had failed to see the police brutality and flawed evidence behind his conviction.

Where the Case Stands in 2026

The courts have spent the years since putting numbers on the damage. In March 2021, Yoon was awarded 2.5 billion won — about $2.2 million — in criminal compensation for his 20 years in prison, and in November 2022 a court ordered the state to pay him roughly 1.8 billion won more in damages. In late 2022, Kim Hyun-jung’s family was awarded 220 million won over the concealment of her remains; they appealed, calling it inadequate. On May 15, 2026, the Seoul Central District Court ordered the state to pay about 77 million won to the children of Hong Seong-rok, a suspect illegally detained for 152 hours in 1987 and coerced into false confessions; he died in 2002, never cleared in his lifetime. His family is appealing, too. Lee Chun-jae, now in his sixties, remains in Busan Prison and has said he has no intention of seeking parole.

Why This Case Still Matters

Hwaseong is the rare case that indicts almost everything at once: a killer who operated freely for five years, an investigation that swept up more than 21,000 innocent men, a torture-built conviction that stole two decades of one man’s life, and a legal calendar that ran out before science caught up. It changed South Korea — the country abolished its statute of limitations for murder in 2015 largely because of these files — and it keeps changing how police interrogations and forensic evidence are scrutinized there. Yoon Sung-yeo’s exoneration is also a warning that travels well beyond Korea: the confession in the file is not always the truth of the case.

Lee Chun-jae confessed to 14 murders and more than 30 sexual assaults, but he is serving time for exactly one crime — the 1994 killing that happened after he left Hwaseong. For the ten women and girls of the county, the law’s clock ran out in silence on April 2, 2006, thirteen years before anyone knew his name.

Related Cases

• The Golden State Killer — a decades-old DNA database match unmasked California’s phantom
• The Monster of Florence — Italy’s countryside serial killings that were never solved
• Bible John — Glasgow’s dance-hall murders and a face police never named

Sources

• The Korea Times — Hwaseong serial killer confesses to 14 murders, 30 sexual assaults
• CNN — South Korean man cleared of killing Hwaseong teenager after 20 years in jail
• The Korea Herald — Hwaseong murders: Korea’s most infamous cold case solved after 33 years
• South China Morning Post — South Korean police apologise over botched Hwaseong murders case
• The Asia Business Daily — Family of Hong Seong-rok, falsely accused in Hwaseong murders, wins partial state compensation
• Wikipedia — Lee Choon-jae

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