The 14-year-old boy in the black school jacket stared at his shoes, his heart pounding, as the policeman accused him of stealing a piece of bread.

Even now, more than 30 years later, Choi Seung-woo weeps when he describes all that happened next.

The policeman yanked down the boy's pants and sparked a cigarette lighter near Choi's genitals until he confessed to a crime he didn't commit.

Then two men with clubs came and dragged Choi off to the Brothers Home, a mountainside institution where some of the worst human rights atrocities in modern South Korean history took place.

Nobody has been held accountable to date for the rapes and killings at the Brothers compound (pictured) in Busan, South Korea, an investigation has claimed. Children are pictured at the camp

A guard in Choi's dormitory raped him that night in 1982 - and the next, and the next. So began five hellish years of slave labour and near-daily assaults, years in which Choi saw men and women beaten to death, their bodies carted away like garbage.

Choi was one of thousands - the homeless, the drunk, but mostly children and the disabled - rounded up off the streets ahead of the 1988 Seoul Olympics, which the ruling dictators saw as international validation of South Korea's arrival as a modern country.

An Associated Press investigation shows that the abuse of these so-called vagrants at Brothers, the largest of dozens of such facilities, was much more vicious and widespread than previously known, based on hundreds of exclusive documents and dozens of interviews with officials and former inmates.

Yet nobody has been held accountable to date for the rapes and killings at the Brothers compound because of a cover-up orchestrated at the highest levels of government, the AP found.

Two early attempts to investigate were suppressed by senior officials who went on to thrive in high-profile jobs; one remains a senior adviser to the current ruling party.

Products made using slave labour at Brothers were sent to Europe, Japan and possibly beyond, and the family that owned the institution continued to run welfare facilities and schools until just two years ago.

Even as South Korea prepares for its second Olympics, in 2018, thousands of traumatized former inmates have still received no compensation, let alone public recognition or an apology. The few who now speak out want a new investigation.

Thousands of children and the disabled were rounded up off the streets (pictured) ahead of the 1988 Seoul Olympics and sent to camps such as the Brothers Home in Busan, South Korea

The current government, however, refuses to revisit the case, and is blocking a push by an opposition lawmaker to do so on the grounds that the evidence is too old.

Ahn Jeong-tae, an official from Seoul's Ministry of the Interior, said focusing on just one human rights incident would financially burden the government and set a bad precedent.

The Brothers' victims, he said, should have submitted their case to a temporary truth-finding commission established in the mid-2000s to investigate past atrocities.

'We can't make separate laws for every incident and there have been so many incidents since the Korean War,' Ahn said.

The government has consistently tried to bury what happened. How do you fight that?

Former inmates, however, cannot forget. One spent months standing quietly in front of the National Assembly with a signboard demanding justice. Choi has attempted suicide several times and now attends weekly therapy sessions.

'The government has consistently tried to bury what happened. How do you fight that? If we spoke up, who would have heard us?' he asked. 'I am wailing, desperate to tell our story. Please listen to us.'

Once an orphanage, Brothers Home at its peak had more than 20 factories churning out woodwork, metalwork, clothing, shoes and other goods made by mostly unpaid inmates.

The sprawling compound of concrete buildings rose above the southern port city of Busan, its inmates hidden from view by tall walls and kept there by guards who carried bats and patrolled with dogs.

The horrors that happened behind those walls are inextricably linked to South Korea's modern history.

The country at the time was still recovering from the near-total devastation of the 1950-53 Korean War, which followed nearly four decades of brutal Japanese colonization.

Once an orphanage, Brothers Home (pictured) at its peak had more than 20 factories churning out woodwork, metalwork, clothing, shoes and other goods made by mostly unpaid inmates

From the 1960s until the 1980s, before democracy, it was ruled by military dictators who focused overwhelmingly on improving the economy.

In 1975, dictator President Park Chung-hee, father of current President Park Geun-hye, issued a directive to police and local officials to 'purify' city streets of vagrants.

Police officers, assisted by shop owners, rounded up panhandlers, small-time street merchants selling gum and trinkets, the disabled, lost or unattended children, and dissidents, including a college student who'd been holding anti-government leaflets.

They ended up as prisoners at 36 nationwide facilities. By 1986, the number of inmates had jumped over five years from 8,600 to more than 16,000, according to government documents obtained by AP.

It was a hell within a hell. The patients had been left there to die Former Brothers inmate Lee Chae-sik

Nearly 4,000 were at Brothers. But about 90 percent of them didn't even meet the government's definition of 'vagrant' and therefore shouldn't have been confined there, former prosecutor Kim Yong Won told the AP, based on Brothers' records and interviews compiled before government officials ended his investigation.

The inner workings of Brothers are laid bare by former inmate Lee Chae-sik, who had extraordinary access as personal assistant to the man in charge of enforcing the rules. The AP independently verified many of the details provided by Lee, now 46, through government documents.

Lee was sent to Brothers at 13 after trouble at school. His first job was in a medical ward. Twice a day, Lee and four others, none of whom had medical training, would try to care for patients, often dousing their open wounds with disinfectant or removing maggots with tweezers.

'People screamed in pain, but we couldn't do much,' Lee said. 'It was a hell within a hell. The patients had been left there to die.'

Stronger inmates raped and beat the weak and stole their food, he said. Lee attempted suicide after a guard at the medical ward raped him.

A year later, he was made personal assistant to chief enforcer Kim Kwang-seok, who like other guards at Brothers was an inmate raised to power by the owner because of his loyalty. Many former inmates remember Kim as the facility's most feared man. The AP tried repeatedly to track Kim down but could not find him.

Adults worked on construction jobs, both at Brothers and off-site. Children sometimes hauled dirt and built walls, but mostly they assembled ballpoint pens and fishing hooks

Lee said he was present when Kim, a short, stocky man with sunburned skin, led near-daily, often fatal beatings at the compound's 'corrections room.' Lee accompanied Kim as he compiled a twice-a-day tally of the sick and dead for the owner; four or five daily deaths were often on the list.

A scene recounted by Lee provides a firsthand account of the efficient, almost casually evil way the facility worked.

One morning, Kim approached owner Park In-keun on his daily jog to report that yet another inmate had been beaten to death the night before. The boy heard Park order Kim to bury the body in the hills behind the compound's walls.

The violence at Brothers happened in the shadow of a massive money-making operation partly based on slave labour.

The factories were ostensibly meant to train inmates for future jobs. But by the end of 1986, Brothers saw a profit from 11 of them, according to Busan city government documents obtained exclusively by the AP.

The documents show that Brothers should have paid the current equivalent of $1.7million to more than 1,000 inmates for their dawn-to-dusk work over an unspecified period.

However, facility records and interviews with inmates at the time suggest that, instead, most of the nearly 4,000 people at Brothers were subject to forced labour without pay, according to prosecutor Kim.

Another probe at the time, quickly scrapped by the government, showed that 'nearly none' of about 100 inmates interviewed received payment. None of 20 former inmates interviewed by the AP received money while at Brothers either, though three got small payments later.

Adults worked on construction jobs, both at Brothers and off-site. Children sometimes hauled dirt and built walls, but mostly they assembled ballpoint pens and fishing hooks.

Choi Seung-woo (left) and Lee Chae-sik (right) talk as they examine what they say was a water tank left from the Brothers Home, a mountainside institution where some of the worst human rights atrocities in modern South Korean history took place, in Busan, South Korea

Some products were tied to other countries. For example, dress shirts made at Brothers' sewing factory were sent to Europe and inmates were trained by employees at Daewoo, a major clothing exporter during the 1980s to the United States and other markets, according to the owner's autobiography.

Park, the owner, said officials from Daewoo had toured the facility before offering a partnership. Daewoo International spokesman Kim Jin-ho said it was impossible to confirm such details because of a lack of records from the time.

Inmates during the 1970s recounted spending long hours tying fishing lines to hooks for packages with Japanese writing on them, for export to Japan.

Kim Hee-gon, an inmate at Brothers for eight years, said he and his colleagues were beaten severely in the early 1970s after thousands of such packages shipped to Japan were returned because they were faulty or missing hooks.

Park Gyeong-bo, who was confined at Brothers from 1975 to 1980, remembered sneaker bottoms produced with the logo of Kukje Sangsa, a now-defunct company that manufactured shoes for the United States and Europe in the 1970s and 80s.

The operation thrived because everybody benefited, except the inmates.

Local officials needed somewhere to put the vagrants they were charged with corralling, so each year they renewed a contract with Brothers that required an inspection of how the inmates were treated and of how the facility was financially managed.

Brothers got government subsidies based on its number of inmates, so it pushed police to round up more vagrants, the early probe found. And police officers were often promoted depending on how many vagrants they picked up.

Two Busan city officials would say only that the facts are difficult to confirm now because the facility closed three decades ago. Heo Gwi-yong, a spokesman for the Busan Metropolitan Police Agency, said he couldn't confirm any details for the same reason.

The owner of Brothers, Park, received two state medals for social welfare achievements and sat on a government advisory panel. His version of his story even inspired a 1985 television drama about a man's heroic devotion to caring for what were called 'bottom-life people.'

Brothers Home owner Park In-keun (right) shakes hands with former South Korean dictator Chun Doo-hwan.

Park eventually served a short prison stint for embezzlement and other relatively minor charges, but not for the abuse at Brothers. When the facility was at last raided in 1987, investigators found a vault in Park's office filled with the current equivalent of about $5 million in U.S. and Japanese currencies and certificates of deposit.

In his autobiography, in court hearings and in talks with close associates, Park has denied wrongdoing and maintained that he simply followed government orders. Repeated attempts to contact him through family, friends and activists were unsuccessful.

The AP, however, tracked down the former second-highest management official at Brothers, Lim Young-soon, who bristled in a telephone interview at descriptions of corruption, violence and slavery at the facility.

Lim, a Protestant pastor now in Australia who is the brother of Park's wife, said Park was a 'devoted' social worker who made Busan better by cleaning its streets of troublemakers. He said Brothers' closure 'damaged national interests.'

Lim acknowledged beating deaths at Brothers, but said they were caused by clashes between inmates. He attributed the facility's high death toll to the many inmates he said arrived there in poor physical and mental health.

'These were people who would have died in the streets anyway,' Lim said.

On his second day at Brothers, still dazed from his brutal rape the night before, Choi waited with other children to be stripped and washed.

He said he watched a guard drag a woman by her hair and then beat her with a club until blood flowed from her head.

'I just stood there, trembling like a leaf,' Choi, 46, said. 'I couldn't even scream when the platoon leader later raped me again.'

Ex-inmates Choi and Lee Chae-sik stood on a concrete-covered former water reservoir that they think is the only remaining physical trace of Brothers

Another time, Choi recalled, he saw seven guards knock down a screaming man, cover him with a blue blanket and stomp and beat him. Blood seeped through the blanket. When it fell away, the dead man's eyes had rolled back into his head.

Death tallies compiled by the facility claimed 513 people died between 1975 and 1986; the real toll was almost certainly higher. Prosecutor Kim interviewed multiple inmates who said facility officials refused to send people to hospitals until they were nearly dead for fear of escape.

'The facility was Park's kingdom, and violence was how he ruled,' Kim said of the owner. 'When you are confined to a place where people are getting beaten to death every day, you aren't likely to complain too much about forced labor, abuse or getting raped.'

Most of the new arrivals at Brothers were in relatively good health, government documents show. Yet at least 15 inmates were dead within just a month of arrival in 1985, and 22 in 1986.

Of the more than 180 documented deaths at Brothers in 1985 and 1986, 55 of the death certificates were issued by a single doctor, Chung Myung-kuk, according to internal facility documents, interviews and records compiled by Kim. Chung, now dead, mostly listed the cause of death as 'heart failure' and 'general weakness.'

Life at Brothers began before dawn, as inmates washed and got ready for mandatory 5:30am prayers, transmitted by loudspeaker from the facility's Presbyterian church. After a morning run, they ate breakfast and then headed to factories or construction sites.

When city officials, foreign missionaries or aid workers visited, a select group of healthy inmates worked for hours to prepare a sanitized version of Brothers for the guests. Guards locked everyone else in their dormitories. Choi said inmates watched hopelessly as these clueless do-gooders trooped through.

On his second day at Brothers, still dazed from his brutal rape the night before, Choi waited with other children to be stripped and washed

On one occasion, Choi (left) recalled, he saw seven guards knock down a screaming man, cover him with a blue blanket and stomp and beat him

'We were trapped in a prison. But who could help us? No one,' Choi said.

Once the doors were locked at 6pm, Choi said, the guards unleashed 'uncontrolled violence' upon the 60 to 100 kids in his dormitory, including frequent rapes.

A principal at a Busan school who once taught at Brothers acknowledged that inmates were held against their will, and even called the facility a massive concentration camp.

However, the principal, who spoke on condition of anonymity because he was worried about his reputation, staunchly defended its practices.

He said severe violence and military-style discipline were the only ways to run a place filled with thousands of unruly people who didn't want to be there.

Park Sun-yi, who had been snatched by police at age nine from a Busan train station in 1980, was one of the few to escape.

She had watched as the guards reserved their most ruthless beatings, the kind where inmates sometimes didn't recover, for those who tried to run. But after five years, she said, she became 'consumed with the thought that my life might be like this forever and that I might die here.'

She and five other girls used a broken saw from the ironwork factory to file away bars on a second-floor window at night, little by little, reattaching them with gum each morning. At last, they squeezed themselves out, scaled a wall embedded with broken glass and fled into the hills.

When she finally walked through the door of her family home in Munsan, she said, her father fainted.

While pheasant hunting, Kim, then a newly appointed prosecutor in the city of Ulsan, heard from his guide about men with wooden bats and large dogs guarding bedraggled prisoners on a nearby mountain.

When they drove there, the men said they were building a ranch for the owner of the Brothers Home in nearby Busan. Kim knew immediately, he said, that he'd stumbled onto 'a very serious crime.'

Former inmate Lee Chae-sik (pictured) walks up a hill behind a row of apartments at the former location of the Brothers Home - an area where he says bodies were buried

Choi said that on one occasion, guards unleashed 'uncontrolled violence' upon the 60 to 100 kids in his dormitory. Residents exercise at a school near an apartment complex at the former location of the Brothers Home

On a frigid January evening in 1987, Kim led 10 policemen in a surprise raid past the facility's high walls, imposing steel gates and gape-mouthed guards. Inside, he found battered and malnourished inmates locked in overcrowded dormitories. The inmates gave the unexpected visitors crisp, military-style salutes.

'I remember thinking, "This isn't a welfare facility; it's a concentration camp,"' Kim, now 61 and a managing partner at a Seoul law firm, said. People lay coughing and moaning in a squalid sick ward, 'just waiting to die.'

After the owner was arrested, he demanded a meeting with Kim's boss, the chief Busan prosecutor, who then supervised Ulsan.

A day later, Busan Mayor Kim Joo-ho, who died in 2014, called Kim to plead for Park's release. Kim said he politely declined and hung up.

At every turn, Kim said, high-ranking officials blocked his investigation, in part out of fear of an embarrassing international incident on the eve of the Olympics.

President Chun Doo-hwan, who took power in a coup after Park Chung-hee was assassinated, didn't need another scandal as he tried to fend off huge pro-democracy protests.

Internal prosecution records reveal several instances where Kim noted intense pressure from Chun's office to curb his probe and push for lighter punishment for the owner. Kim had to reassure presidential officials directly and regularly that his investigation wouldn't expand.

Park Hee-tae, then Busan's head prosecutor and later the nation's justice minister, relentlessly pushed to reduce the scope of the investigation, Kim said, including forcing him to stop his efforts to interview every inmate at Brothers.

Park, a senior adviser to the current ruling party, has repeatedly denied AP interview requests. His personal secretary said Park can't remember details about the investigation.

A prosecutor collected bank records and financial transactions indicating that, in 1985 and 1986 alone, the owner of Brothers embezzled what would be the current equivalent of more than $3million. Choi Seung-woo examines a lock on what he says was a water tank left from the Brothers Home

Despite interference, Kim eventually collected bank records and financial transactions indicating that, in 1985 and 1986 alone, the owner of Brothers embezzled what would be the current equivalent of more than $3million.

That came from about $10million of government subsidies meant to feed and clothe the inmates and maintain the facilities.

However, Kim said, the chief Busan prosecutor forced Kim to list the embezzlement as nearly half the amount he had actually found so that a life sentence couldn't be pursued under the law at the time.

Kim said his bosses also prevented him from charging the owner, Park, or anyone else for the suspected widespread abuse at the Brothers compound, and limited the prosecutor to pursuing much narrower abuse linked to the construction site Kim found while hunting.

Kim demanded a 15-year prison term for Park. After a lengthy battle, the Supreme Court in 1989 gave Park 2{ years in prison for embezzlement and violations of construction, grassland management and foreign currency laws.

He was acquitted of charges linked to off-site abuse. Only two guards received prison terms, one for 1{ years and another for eight months.

After prison, Park continued to earn money from welfare facilities and land sales. The Brothers site was purchased in 2001 by a construction company for what would now be about $27million, according to a copy of the land sale shown to the AP.

One of Park's daughters operated a school for troubled kids that closed in 2013. His family in 2014 sold a home for the severely disabled.

Kim Yong Won, the former prosecutor who was in charge of the Brothers Home case, speaks during an interview at his office in Seoul

It finally closed its gates in 1988. In the 1990s, construction labourers dug up about 100 human bones on the patch of mountain just outside where it stood, according to one of the workers who found the bones, Lee Jin-seob.

Blankets covering the bones and the lack of burial mounds made Lee think they'd been buried informally and quickly. It's unclear what happened to the remains.

On a recent trip to the site, which is now covered with tall apartment buildings, ex-inmates Choi and Lee Chae-sik stood on a concrete-covered former water reservoir that they think is the only remaining physical trace of Brothers. Both recalled the sight of guards carrying corpses into the woods.

'There could be hundreds of bodies still out there,' Lee said, pointing toward the steep slopes.

Inmates released from the facility ended up homeless and in shelters and mental institutions; many struggle with alcoholism, depression, rage, shame and poverty.

Choi, whose back is covered by a large tattoo from his time in a gang after he left Brothers, was imprisoned for assaulting a policeman.

The few former inmates who have begun speaking out want justice: an apology and an admission that officials encouraged police to kidnap and lock away people who shouldn't have been confined.