True Crime (2) Frog Boys mystery

Korea Herald

a day ago

Have you heard of the Frog Boys? No, it's not some quirky K-pop group — it's a name tied to one of Korea's most haunting mysteries.
In the early 1990s, five young boys set out on a forest excursion and never came home. Their sudden disappearance sent shockwaves across the nation. Their faces became impossible to avoid, plastered everywhere from milk cartons to detergent boxes.
It was a story that no Korean who lived through that era could escape.
In this episode of True Crime, we take you back to March 1991, when five boys mysteriously disappeared at the same time in a small, rural village in South Korea.
The boys
Who were the boys?
Their faces were everywhere, plastered on walls and printed on various supermarket products, but wherever they were seen, the description and details were almost always identical to the flier you see here.
At the top, there's a reward: 42 million Korean won. Back in 1991, with inflation, that would've been worth about $81,000 at today's rates.
And these are the photos of the boys, frozen in time, forever in adolescence.
The youngest is Kim Jong-sik, just 10 years old. He's wearing a purple top in his picture. A brief description reads, 'a chubby, round face with a slight gap between his front teeth.'
Next is Kim Yeong-gyu, age 12, noted as being 'a little chubby' with scars on both his forehead and the bridge of his nose.
Woo Chul-won, age 14, is the oldest. He's described as 'skinny, long-faced, with a small 1-centimeter scar between his eyebrows.'
Then there's Jo Ho-yeon, age 13, described as 'skinny, with upper front teeth that protrude.'
And finally, the youngest Park Chan-in, 11. He stands out with his red shirt and smiling face. The description adds, 'skinny, long face, big ears and thick bottom lip.'
The flyer also states that all five boys went missing on March 26, 1991. That's the day we're traveling back to now.
The year was 1991. The Gulf War had just ended, and in the US, Rodney King was brutally beaten by Los Angeles police, captured on videotape. The Soviet Union was still around, but had just a few months before its dissolution in the final days of the year.
In South Korea, democracy had returned after years of military dictatorship. On March 26, the country took another historic step by holding its first local government elections in three decades.
The city of Daegu, in the country's southeast, wasn't particularly known for much but its strong dialect and conservative political leanings.
For the boys in the village of Seongseo, none of this mattered. It was a special day because school was closed, and they had all day to play.
The father of Woo Chul-won, the oldest of the boys, remembers the day vividly.
From early morning, his son had been playing outside.
Just as the father was getting ready to go cast his vote in the historic election, Chul-won, or Won, as the father lovingly called him, burst into the house. The boy grabbed his jacket and was about to leave, when his father stopped him and asked if he wanted to come and watch him vote.
But the boy declined, his mind already fixed on the little adventure to a nearby hill that he had planned with friends.
That was the last time his father saw him.
From here, the boys' journey can only be pieced together through fragments of memory — the accounts of those who crossed paths with them that day.
Near a supermarket, the five kids ran into the older brother of one of their company, the 13-year-old Jo Ho-yeon. They told him they were heading to the mountain and Jo advised them to make sure and come home before it got too late.
On their way to the mountain, they passed through a school playground. There, they bumped into another village boy and invited him to join their adventure to hunt for salamander eggs.
The friend considered joining them, but decided not to and headed home. He later said he saw them crossing the playground and climbing the stairs in the direction of the mountain.
Near the foot of the mountain, more witnesses reported seeing the boys. They were carrying sticks and milk cartons, probably to collect the salamander eggs they hoped to find.
Sometimes, when something bad has happened to their children, parents just know. It may have been this unexplainable parental instinct.
Around 11 a.m., Kim Jong-sik's mother felt a sudden surge of anxiety. Unable to shake the feeling, she started searching for her son, checking all his usual hangouts.
Lunchtime came and went, and her worry deepened. It was unusual for her son not to come home for lunch.
By afternoon, fear had fully set in. Other parents, too, were searching. They went to the police station, pleading with officers to take action.
The police were not as concerned as the parents. After all, the boys were together. They must have lost track of time while playing — that was their thought.
But the parents knew their children better than anyone. They said their kids were dependable and punctual, especially when it came to the boys' Taekwondo classes, which they loved, and were supposed to attend that day.
The Taekwondo instructors had even offered to let them skip class since it was election day, but the boys had insisted on attending.
Missing class — and staying out so late — was completely out of character.
Late that night, the parents and police officers went up the hill, calling out the kids' names. But it was too dark to keep looking. So they decided to pick up their search the next morning.
Many of them thought the kids might just come back after spending a rough night away from home.
Nationwide search
Days passed, but none of the five boys came home.
While their fathers combed the mountain, checked every bus and train station in the region and traveled to even more distant places in search of any clue to their whereabouts, the mothers stayed home, glued to the phone, waiting for any news. By this time, the disappearance of the five boys from a small village had become major news, drawing attention from the public.
One day, a call came in.
Mysterious caller said, 'Your sons are with me. Prepare 4 million won and put it on the railroad tracks at Daegu Station.'
In 1991, 4 million won was the equivalent of around $7,000 in today's money.
The parents clung to the desperate hope that handing over the money would bring their boys home safely. So, they did exactly what the mystery kidnapper asked them to do.
But nobody showed up on the tracks that day.
This call marked the beginning of many more prank calls that followed. Each ring sparked hope that was extinguished.
One day, Kim Jong-sik's mother answered a phone call that left her stunned. By then, she was accustomed to prank calls and was rarely surprised by them.
'Mom.'
The voice, eerily similar to her son's, made her heart pound.
When she asked if it was Jong-sik, the caller replied, 'Yes,' and the call ended.
Later, a voice expert analyzed a recording of the call, comparing it to a recording the boy's mom had of her son singing. The result was disappointing: The two voices seemed similar, but the phone recording was too short to determine anything conclusively.
All five fathers quit their jobs, devoting themselves entirely to the search for their missing children. They converted a battered truck into a mobile billboard, covering it with large photos of their sons.
Train stations, department stores and bus terminals became their constant destinations. Day and night, they distributed flyers bearing their children's faces.
The boys' disappearance consumed the fathers' lives, leaving no space for a break. Even sharing a bottle of soju, a cheap liquor, felt impossible without feeling guilty.
"What are you so happy about to be drinking?" was the question the fathers dreaded most.
The father's desperate search moved many hearts around the country, prompting media outlets to cover the unsolved case extensively. Although the boys had gone to search for salamander eggs, the media, unfamiliar with the creature, reported they were looking for frog eggs. This is why the case became known as the "missing frog boys."
Soon, the entire nation was gripped by the story.
Everyone knew their names and hoped for their return. The police search centered on Bulmigol, a particular spot on Waryongsan, the mountain near the boys' home.
Even South Korea's president, Roh Tae-woo, ordered a full investigation, and nearly 300,000 people joined the search.
Local businesses pitched in, too. The boys' faces appeared in unexpected places like cigarette boxes, milk cartons and telephone cards — even boxes of Super Ti laundry detergent.
But time was not on their side. Three years passed by, but the boys were still missing.
The fathers believed they had done everything they could. Eventually, the time came for them to face the difficult decision to end their search.
The fathers said in a statement: 'We've given up our careers and searched the entire country. We can't go on. We're leaving the search to the authorities and hoping for a miracle. Thank you to everyone who supported us."
Just as the parents were trying to go back to their ordinary lives, a bombshell shook them in 1996.
Professor Kim Ga-won, a psychologist who lectured at KAIST, a prestigious science and technology university, claimed that Kim Jong-sik's father was the culprit. He also claimed that he had conducted an investigation of his own since 1993. His theory was that Kim Jong-sik's dad killed the boys and buried their bodies beneath his house.
One might think, "Who would believe such a baseless accusation?"
Well, the police did. Or, at least, they were desperate enough to give it a shot.
They dug up the ground beneath Kim's house, specifically targeting the washroom area that the professor pinpointed in January 1996. In the washroom, they found Kim Jong-sik's shoe, but nothing else. It was the boy's home, after all, so the discovery of the shoe did not tell them much.
The discovery
Just when the boys' story slowly started to fade from Korea's public consciousness, the boys reappeared.
On Sept. 26, 2002, 11 years after they went missing, the boys were found, as remains on Waryongsan, just one kilometer from the heavily investigated Bulmigol area.
This was less than a year after Kim Jong-sik's father, the one who was falsely accused, died in October 2001. Still in his 40s, he died of cancer.
The boys were found by a forager who was collecting acorns. Their remains were not buried deep — some had been barely covered with soil.
One may wonder, if a forager could find them so easily, why couldn't the over 300,000 people who'd been looking for them?
The location could be part of it. They were found off the beaten track in Sebanggol, separated by a ridge from the heavily searched Bulmigol.
When the bodies were found, the country was sad but also hopeful that they would finally learn what happened to the boys, some long-awaited closure.
But that's not what happened. Instead, their discovery only added to the confusion.
Initially, some police officers attributed the deaths to hypothermia caused by the cold and rainy weather.
On the day they went to the mountain, the temperature ranged from a low of 3.3 degrees to a high of 12.3 degrees, with rain starting in the evening, making it chillier.
But this explanation was not believed by many in the public or by the boys' families.
The families believed that if they had frozen to death, there was no way that they would not have been discovered by someone 11 years ago. They claimed the police were just trying to close the case quickly as an unfortunate accident.
The parents also said the condition of the corpses made it hard to believe that cold weather was the killer.
Four sets of remains were tangled together in the dirt, along with five pairs of kids' sneakers and around ten pieces of clothing. Among them, one of the corpses had dental work resembling that of Jo Ho-yeon. Woo Chul-won's skull was enveloped by his sweatshirt, while the legs of Kim Yeong-gyu's tracksuit bottoms were knotted.
The results of a closer forensic examination came out about a month later, concluding that the boys had been murdered.
Paek Jung-sik, a forensic official, said, 'Three of the skulls bore distinct, man-made holes, likely inflicted at the time of death.'
A flier seeking information about the deaths of the children, created after the bones were found, noted that the skull of one of the boys had rectangular-shaped holes measuring between 1.4 and 2 millimeters. Additionally, there were 15 smaller puncture marks around the holes.
The forensic team added that the boys likely had been murdered from repeated blows to the head with an unidentified weapon or weapons. Regrettably, the investigation failed to pinpoint the perpetrator(s) or the murder weapon(s).
On March 26, 2004, exactly 13 years after they went to the mountains, the boys' remains were cremated and laid to rest. The families, however, kept their skulls in the hope that one day they would serve as evidence that could help convict the killer.
Two years later, in 2006, the case exceeded the statute of limitations.
Unanswered questions
This is not the end of the Frog Boys' story.
In 2022, the case gained renewed attention online.
An anonymous post claimed that the author knew what was used to kill the boys: a vernier caliper, a measuring device used for measuring the size of objects. The post also suggested that a group of delinquent teens in the neighborhood might have been involved, without giving any substantial evidence to back the claim.
Despite the lack of evidence, the post gained public attention, and MBC's 'PD Notepad,' an iconic investigative TV journalism program in South Korea, featured an episode about the case in 2022.
The show suggested that while many young students used to hang out on the mountain, possibly sniffing glue to get high, it was unlikely they would have vernier calipers — it was not a tool commonly used at the nearby vocational high schools.
But the show did consider the possibility that the weapon was a pair of calipers or pruning shears, based on experiments with forensic scientists.
A scientist said the 'X' shaped holes on one of the skulls are not easily made with one of those two implements.
The show also raised the possibility of military involvement, with a witness claiming to have seen a soldier in a red hat with an eagle emblem interacting with the five boys. The witness said the soldier told the kids to play somewhere else, and the kids asked if he could give them a salamander egg.
But the military claimed there were no training exercises on that day due to the election, which was a holiday.
Because the case is of such great public interest, it remains officially open. The investigation is the responsibility of the Daegu police's cold case unit.
The father of Chul-won, the oldest of the five boys, told the media that the parents used to pray for the kids to appear in their dreams and reveal what had happened — or for the killer, or someone who knew the truth, to come forward and finally relieve their consciences in their later years. They desperately wanted answers.
But after so many years, all they want now, he said, is for the boys to rest in peace.
This article is a written adaptation of The Korea Herald's new podcast True Crime. You can listen to the full episode on Spotify and Podbbang. ― Ed.