More evidence of horrendous human rights abuses within Syria’s prison system has emerged - this time involving women and children.

Last week, Amnesty International revealed that President Bashar al-Assad’s government executed up to 13,000 prisoners at a prison near Damascus since 2011.

The human rights organisation said inmates were allegedly executed after “sham trials” lasting no more than couple of minutes.

It said groups of up to 50 people were taken out of their cells at the Saydnaya prison - known to detainees as “The Slaughterhouse” - once or twice a week and summarily hanged.

Tens of thousands of people have disappeared into jails operated by the Assad regime during the country's uprising and civil war.

Aleppo ordeal

Today, a woman and a teenager - who were among many enticed to leave rebel-held besieged areas by the regime only to disappear into government jails - shared accounts of their ordeal in an Aleppo prison.

The teenager, a 15-year-old girl, told Sky News she was stopped with her father after they crossed in to government-held territory.

"They held us at the checkpoint and arrested my father," she said. "They made him kneel on the ground then they took him inside to the detention room. They tortured him with a knife.

"They took me with him and said: 'You're a terrorist and you're a sniper.' I denied it but they said there is a report and we're sure of this information. To scare me they had my father kneel on the floor and grabbed him by his hair."

Once in jail, the teenager discovered many other women and children being held against their will and subject to torture.

"There were children with their mothers, and even the children were tortured. They would beat them and make them stand against the wall as punishment," she said.

Gulag jail system

Syria's Assad regime has rejected claims it is operating a Gulag system of jails in which tens of thousands have disappeared, been tortured and often never emerged again.

But more and more evidence is emerging to disprove those denials.

Another woman who spoke to Sky News claims she saw men being tortured.

"They would beat them and they wouldn't have a chance to breathe, they would gasp or something like that, and it's a really terrible sound," she said.

"And we felt like those who were tortured for a while would lose their voice. And at first we didn't know, but then we understood that whoever's voice faded away or disappeared, that means he's dead."

The same woman claimed she saw children as young as four being beaten until their hands bled.

Both women were held for a number of months and then released as part of prison exchanges. They were the lucky ones. Tens of thousands of Syrian civilians have disappeared into Assad's jails, and never been seen again.