Syrians search notorious Assad jail for underground cells while freed prisoners rejoice

Syrians on Monday celebrated the overthrow of President Bashar al-Assad, as thousands of detainees were freed from his notorious jails while families and rescuers searched for those still missing.

Powerful images have emerged showing people, including women and children, being freed from prisons across the country after the toppling of Assad, whose brutal regime saw hundreds of thousands of political prisoners disappear into jails where many faced torture and death.

While Assad was in Moscow having fled the country, one facility known as the “human slaughterhouse” was being searched for signs of secret underground cells.

Men in one video verified by NBC News could be seen cheering as they were released by fighters who shot the lock off the doors then entered Saydnaya prison near Damascus, in the hours after rebel forces captured the Syrian capital.

In another video, a little boy appeared to be be seen toddling out of a cell as women around him rejoiced, with some expressing confusion after being told they'd been freed and asking for their belongings and their identification cards.

But harrowing stories also emerged, and rescue teams rushed to search Saydnaya after receiving reports of detainees being held in "hidden underground cells," with families also racing to the facility in hopes of finding their loved ones there.

The White Helmets rescue organization said it had deployed five specialized emergency teams to search for prison cells believed to be hidden underground at the notorious prison, citing survivors' accounts.

Those teams are compromised of search and rescue units, wall-breaching specialists, iron door-opening crews, trained dog units, and medical responders," the White Helmets said in a statement shared on X, adding that the crews were "well trained and equipped to manage such complex operations."

As of early Monday, the group said there was "no evidence confirming the presence of detainees in the basements or cellars of the prison,” with search efforts still underway. It offered a $3,000 reward for “anyone who provides information that helps locate secret prisons and detention centers where detainees are held.”

The prisons are infamous for their harrowing conditions, with human rights groups long warning that Assad oversaw a system of torture, abuse and killings to maintain his grip on the country.

'They said he was killed'

For more than a decade Abdulaziz Almashi thought a close family member was dead. He told NBC News on Monday of his shock when he learned that his second cousin had in fact been locked inside one of Assad's prisons.

"They said he was killed by 'terrorists'," said Almashi, 39, a refugee in London from the Syrian city of Manbij who founded the organization Syria Solidarity Campaign. "It turned out, he's alive."

Almashi said his second cousin, now in his early 30s, had been carrying out mandatory military service when the Syrian revolution began. He tried to flee, not wanting to fight for Assad, but was captured.

Authorities told Almashi's family in 2012 that he was killed on the battlefield, filling them with grief, despair — and shame.

"Can you imagine how we thought about it?" said Almashi. "Like, how could someone from our family die from fighting for Assad? He’s on the wrong side of history."

It was only on Sunday, when his second cousin emerged from his prison cell emaciated and raced to find his family, that they learned he had been incarcerated the entire time.

"It’s unbelievable," Almashi said. "And will he ever recover? That is the question."

And Almashi, who is desperate to return to Syria to be reunited with his loved ones, stressed that his family's harrowing account is just one of many.

"Everyone that has come out of prison has stories," he said.

Tens of thousands of people have been "forcibly disappeared" in Syria, according to Amnesty International, with Assad's overthrow raising the prospect "that they could finally discover the fate of their missing loved ones, in some cases decades later," the organization said in a statement Sunday.

In a 2017 report called "Human Slaughterhouse" Amnesty described the brutal conditions of the Saydnaya military prison, marked by "killings, torture, enforced disappearance, mass hangings and extermination of detainees."

Almashi said he was amazed his loved one survived his harrowing ordeal.

“Why would you call his family and say he’s dead?" he said. "Because you know that he will end up dead in a prison anyway."

Salem Alaya, who fled Syria and settled in Britain as a refugee in 2014, said he cried as he watched videos of people being freed from prison cells.

"When my dad passed away, I did not cry like I did yesterday," said Alaya, 38, noting that he never got to say goodbye to his father, who died in 2016.

"I was just crying," he told NBC News.

Alaya, who helps run a Facebook group supporting Syrian refugees arriving in London, said he had several friends and loved ones, including two uncles, who had been held as political prisoners in Syrian jails for years with no word on their whereabouts or wellbeing.

"Maybe they died. Maybe they disappeared. Maybe they have been killed inside the prison," he said. "I hope that we can hear about them."

This story first appeared on NBCNews.com. More from NBC News:

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