The Syrian civil defence group known as the White Helmets says it is investigating reports from survivors of the country's notorious Saydnaya prison that people are being detained in hidden underground cells.
As Syrian rebels led by the Islamist group Hayat Tahrir al-Sham (HTS) captured city after city on the road to Damascus, forcing Bashar al-Assad to flee the country, they also opened the doors of the regime’s notorious prisons, into which upwards of 100,000 people disappeared during nearly 14 years of civil war.
Verified videos from Damascus showed dozens of women and children being held in cells, the rebels opening the doors and telling them not to be afraid.
Rebels reportedly liberated detention facilities, releasing inmates who were long thought to be lost. Videos from Damascus show women and children being freed from cells, with the rebels reassuring them, “Don’t be afraid.”
One of the liberated prisoners, a young man, shared his harrowing experience with Al Jazeera, recounting his time in captivity: “I had no name in the prison, just a number. I lost my identity, my name and my character. I was taken by the regime, and my family assumed I was dead.”
Many prisoners, he revealed, were detained without their families knowing, spending years behind bars in secret.
Another harrowing account comes from a group of men who were rescued on the day they were scheduled for execution. “Now we are standing in the heart of Damascus,” one man declared, standing with three others. “I swear to God Almighty, this man and I were scheduled to be hanged on this day only 30 minutes ago. I swear to God Almighty, 54 men were to be executed today.”
Bewildered and elated prisoners poured out of Syrian jails on Sunday, shouting with joy as they emerged from one of the world's most notorious detention systems and walked to freedom following the collapse of Bashar al-Assad's government.
All across Syria, families wept as they were reunited with children, siblings, spouses and parents who vanished years ago into the impregnable gulag of the Assad dynasty's five-decade reign.
Newly freed prisoners ran through the Damascus streets holding up the fingers of both hands to show how many years they had been in prison, asking passers-by what had happened, not immediately understanding that Assad had fallen.
"We toppled the regime!" a voice shouted and a prisoner yelled and skipped with delight in one video. A man watching the prisoners rush through the dawn streets put his hands to head, exclaiming with wonder: "Oh my god, the prisoners!"
Throughout the civil war that began in 2011, security forces have held hundreds of thousands of people seized into detention camps where international human rights organisations say torture was universal practice. Families were often told nothing of their loved-ones' fate.
As insurgents seized one city after another in a dizzying eight-day campaign, prisons were often among their first objectives. The most notorious prisons in and around Damascus itself were finally opened on the uprising's final night and the early hours of Sunday.
One grey-haired man in a video uploaded by Step News Agency leapt into the arms of relatives in a sudden, disbelieving hug, the three men clasping each other and sobbing with joy before one fell to his knees, still clutching the freed man's legs.
The pan-Arab Arabiya news channel showed a family arriving in Damascus by car from Jordan to meet their newly released son, the elderly mother's voice breaking with emotion as she told the interviewer he had been freed after 14 years.
Reuters was not immediately able to verify the locations of some of the videos, though no one disputed that prisons were opened across the country
In what was purported to be the women's block at Sednaya prison on the Damascus outskirts, perhaps the most notorious in the country, a rebel recorded the moment he reached cells and pulled open the doors for prisoners who seemed to have had little idea they were about to be freed.
"May God honour you!" a woman shouted to the men freeing her. As they left their cells a toddler could be seen walking the corridor, having apparently been held in the prison along with his mother.
"He (Assad) has fallen. Don't be scared," a voice shouts, trying to reassure the prisoners that they faced no more danger.
In another video, a deafening roar erupted as rebels marched down a corridor, said to be in the prison at Mezzeh air base southwest of the old centre of Damascus. Prisoners leaned through the bars at the top of doors and banged on the sides of their cells as shouts of joy echoed all around.
One video showed a shaven-headed man squatting on his heels, trembling and barely able to answer the rebels asking his name and where he was from.
Thousands of Syrians have over the years been brusquely informed by authorities that their relatives had been executed, sometimes years earlier.
The United States said in 2017 it had evidence of a new crematorium built at Sednaya especially to dispose of bodies of thousands of inmates hanged during the war.
Some of the most disturbing information about Assad's prison system came with thousands of photographs smuggled out of Syria by a military photographer codenamed Caesar who defected to the West in 2013.
His photographs of thousands of killed detainees showed clear marks of torture and starvation and for many families provided the first evidence that imprisoned relatives were dead.
A few miles from Sednaya early on Sunday, a stream of freed prisoners were recorded walking towards Damascus, many lugging sacks of belongings on their backs, and chanting "God is great!"
Writing on X, the group says it has deployed five "specialised emergency teams" to the prison, who are being helped by a guide familiar with the prison's layout.
Saydnaya is one of the prisons to have been liberated as rebels took control of the country.
Authorities in Damascus province reported that efforts were continuing to free prisoners, some of whom were "almost choking to death" from lack of ventilation.
The Damascus Countryside Governorate has appealed on social media to former soldiers and prison workers in the Assad regime to provide the rebel forces with the codes to electronic underground doors.
They say they have been unable to open them in order to free "more than 100,000 detainees who can be seen on CCTV monitors".
Video has been circulating online and through news outlets including Al Jazeera of what appears to be efforts to access lower parts of the prison.
In it, a man can be seen using a type of post to knock out a lower wall, revealing a dark space behind.
Other footage has shown prisoners being freed - including a small child being held with his mother. He is shown in a video of women being released that was posted by the Turkey-based Association of Detainees and The Missing in Sednaya Prison (ADMSP).
"He [Assad] has fallen. Don't be scared," a voice on the video says, apparently trying to reassure the women that they were now safe.
Video verified by AFP showed Syrians rushing to see if their relatives were among those released from Saydnaya, where thousands of opposition supporters are said to have been tortured and executed under the Assad regime.
Rebel forces have swept across Syria, freeing prisoners from government jails as they went.
Throughout the civil war, which began in 2011, government forces held hundreds of thousands of people in detention camps, where human rights groups say torture was common.
On Saturday Hayat Tahrir al-Sham (HTS) said it had freed more than 3,500 detainees from Homs Military Prison as the group took over the city.
As they entered the capital hours later early on Sunday, HTS announced an "end of the era of tyranny in the prison of Saydnaya", which has become a by-word for the darkest abuses of Assad's era.
In a 2022 report, ADMSP said Saydnaya "effectively became a death camp" after the start of the civil war.
It estimated that more than 30,000 detainees had either been executed or died as a result of torture, lack of medical care or starvation between 2011 and 2018. Citing accounts from the few released inmates, at least another 500 detainees had been executed between 2018 and 2021, it said.
In 2017, Amnesty International described Saydnaya as a "human slaughterhouse", in a report that alleged that executions had been authorised at the highest levels of the Assad government.
The government at that time dismissed Amnesty's claims as "baseless" and "devoid of truth", insisting that all executions in Syria followed due process.
ADMSP A toddler, no more than 3 or 4 years of age, walks through an open cell door.ADMSP
In one clip, a young child wanders through an open cell door
Video cited by Reuters showed rebels shooting the lock off Saydnaya prison gate and used more gunfire to open closed doors leading to cells. Men poured out into the corridors.
Other footage, which the Reuters news agency says was taken on the streets of Damascus, appears to show recently freed prisoners running down the street.
In it, one asks a passer-by what happened.
"We toppled the regime," they respond, eliciting an excited laugh from the former prisoner.
Of all the symbols of the repressive nature of the Assad regime, the network of prisons into which those expressing any form of dissent were disappeared cast the longest and darkest shadow.
In Saydnaya, torture, sexual assault and mass execution were the fate of thousands. Many never re-emerged, with their families often not knowing for many years whether they were alive or dead.
One of those who survived the ordeal, Omar al-Shogre, told the BBC on Sunday about what he endured during three years of incarceration as a teenager.
"I know the pain, I know the loneliness and also the hopelessness you feel because the world let you suffer and did nothing about it," he said.
"They forced my cousin whom I loved so much to torture me, and they force me to torture him. Otherwise, we would both be executed."
ADMSP woman is released from prisonADMSP
Women are freed from the notorious Saydnaya prison
A Syrian human rights network estimates that more than 130,000 people have been subjected to detention in these conditions since 2011. But the history of these intentionally terrifying institutions goes back much further.
Even in neighbouring Lebanon, the fear of being disappeared to a Syrian dungeon was pervasive during the many years that Damascus was the dominant foreign power.
The deep hatred of the Assad regime - both father and son - that simmered under the surface in Syria was due in large part to this industrial-scale mechanism of torture, death and humiliation that was intended to frighten the population into submission.
For that reason, rebel factions in their lightning drive through Syria that toppled President Assad made sure in each city they captured to go to the central prison in each one and release the thousands held there.
The image of these people emerging into the light from a darkness that had shrouded some for decades will be one of the defining images of the downfall of the Assad dynasty.
The International, Impartial and Independent Mechanism (IIIM) recently published a report that sheds light on the scale of abuse within Assad's detention system. The report, based on interviews with over 300 former detainees, provides a stark description of the horrors faced by Syrians detained by the regime. Physical and psychological abuse was commonplace, with detainees subjected to beatings, stress positions, sexual violence, and torture. The conditions were appalling, with overcrowding, insufficient food and water, and a complete lack of medical care.