Islamic State militants imprisoned Yazidi women in a dungeon buried underneath the desert in northern Syria, it has emerged.
Sky News reporters were shown a small makeshift prison cell hidden beneath the sand, where dozens of women from the Yazidi minority group are believed to have been held. It is not known where they are now.
Yazidism is an offshoot of Zoroastrianism, which blends ancient religious traditions with both Christianity and Islam. According to ISIS doctrine, they are "devil-worshippers", and members of the group have been systematically persecuted by militants.
Last month, a number of mass graves were found in the Iraqi town of Sinjar, believed to contain the bodies of over 200 Yazidis.
Hundreds of thousands of residents were forced to flee from Sinjar when Kurdish troops withdrew in August last year, leaving them vulnerable to attack, and thousands were killed. Many women and girls were taken as sex slaves, and horrifying accounts have emerged of their treatment at the hands of ISIS militants. A 22-year-old Yazidi woman told CNN in October that she was raped by 12 militants while in captivity, who believed that a woman would become Muslim if she was raped by at least ten men.
In March of this year, the office of the United Nations High Commissioner for Human Rights said the persecution of the Yazidi people may qualify as genocide.
Among the crimes it said had been perpetrated against the minority were the "brutal and targeted" killing of hundreds of men and boys in Nineveh province last August, and the rape of girls as young as six years old. Young boys have also been taken to be trained as militants.
An activist who has interviewed a number of those who have fled captivity told NBC News in November that some Yazidi women are being sold by ISIS fighters for as little as $10 or a packet of cigarettes.
Khider Domle said that women are often traded between militants multiple times, and used to demand ransom sums from their families.
It is thought that around 2,000 Yazidi women are currently being held captive by jihadists.
