Horror stories have begun to emerge in the wake of the freeing of several hundred captives of the Islamic State of Iraq and Greater Syria (ISIS)  in Aleppo.
Rebel groups from the mainstream Free Syrian Army, the conservative Islamic Front, and several independent Islamist groups have been locked in a campaign against the hard-line Al-Qaeda militants of ISIS over the past week .
Wednesday’s rebel capture of a central detention facility used by ISIS in Aleppo  – a children’s eye hospital in the neighborhood of Qadi Askar – led to freedom for several hundred people, who have begun to tell their stories of captivity.
Two eight-minute videos posted on YouTube by media activists from the city featured interviews with former captives of the militant group.
In one, Milad Shehabi, a prominent media activist who was himself detained last month, described how the treatment by the ISIS militants was “worse than [the regime’s] Air Force intelligence.” 
Shehabi said he spent his first 13 days of captivity blindfolded, and in solitary confinement in a 1-by-1.5 meter room.
“They stamped on me their military boots. They stepped on my neck with a military boot, and said, ‘you dogs, you want a revolution?’” Shehabi recalled.
He said at one point, prisoners would voice their hope that the detention facility would be bombed by regime aircraft to end their ordeal.
“We’d pray for the planes to hit us, to release us from this torture ... revolutionaries since the beginning of the uprising, and this is what happens to us?”
He said that he later became aware that the facility contained 11 holding cells, each with 20 to 35 detainees.
In addition to civilian detainees, some of whom were minors, various members of rebel groups fighting the regime of President Bashar Assad  were taken prisoner for various periods of time by ISIS militants, he said.
“They were liquidating the Free Syrian Army, one battalion at a time,” Shehabi said. “They would have continued until the whole country was under their control, if it hadn’t been for the unification of the rebels recently.”
In the other video, several former prisoners detailed their experiences .
One said he is a Free Syrian Army  commander from Maaret al-Numan, who was taken prisoner after organizing a demonstration late last month, demanding that ISIS release a leading FSA commander.
Another captive said he was taken solely because he was carrying an identification card from the Ahfad al-Rasoul (Grandsons of the Prophet) rebel battalion.
He said his ISIS captors taunted him with accusations such as “You’re not Grandsons of the Prophet, you’re Grandsons of the Devil.”
While ISIS is militantly Islamist, it views any competing group, even if it is Islamist, as insufficiently pious  for not adhering to its ultraconservative version of Islam.
The former prisoners tell their interviewer of how various categories of detainees were summarily executed, sometimes in front of them.
“They took a 15-year-old boy, and accused him of being a shabbih [pro-regime thug],” one man said.
“They pulled out his fingernails, and got him to finally confess to raping three women – a 15-year-old, only this tall,” the man said, gesturing to indicate the ridiculousness of the charge.
“Two Kurds were tortured and accused of being members of the PKK,” another detainee said, referring to the Kurdish party that is seen as being in league with the Syrian regime. “They never confessed ... One of them was shot right in front of us; they put a pistol to his head and shot him. The guy couldn’t even speak Arabic.”
Captives of ISIS were often forced to drink salty water, and kept for days at a time blindfolded, the detainees said. They were often forced to pray without being allowed access to water to perform ablutions beforehand, the captives alleged.
“Sometimes they made us pray with our hands tied behind our back,” one man says.
The captive rebels were often berated with the question, “What’s the difference between you and the regime?” one man alleged.
A third, much shorter video purported to show a 10-year-old who was liberated from his ISIS captors. The boy was clearly traumatized and hardly able to answer questions about his detention.
Cilina Nasser, a researcher in the Middle East and North Africa Program of Amnesty International, based in London, said the organization was very concerned about the fate of remaining detainees held by ISIS as the campaign against the extremist group intensifies.
Some opposition sources believe that up to 1,500 people were held by ISIS before the offensive against it .
The organization produced a report last month on the situation in ISIS detention facilities in Aleppo and the city of Raqqa, based on the testimony of former detainees.
She said the testimony of former detainees was consistent with regard to uncompromising hostility of ISIS members to the Syrian uprising.
Nasser said that the emirs, or leaders of ISIS, regularly told detainees that “we’re not here for freedom,” and that “this revolution is an infidel revolution.”
The group doesn’t have a global figure for the number of detainees of ISIS throughout Syria, and ISIS is believed to administer a number of secret detention facilities, in contrast to the Qadi Askar facility, which the public in Aleppo was well aware of.
“We’re very concerned that in other areas where ISIS is feeling the heat and losing its battles, it might lead to killings in these detention centers,” Nasser said.
Asked under what conditions individuals were being freed by their ISIS captors, Nasser said that the reasons were unclear.
“It’s similar to the treatment by the authorities, when a person is detained and then released, and they don’t really know why.”