The Syrian Observatory for Human Rights said the execution took place in August or September in an IS-controlled rural area in the east of the central province of Hama.

It was the latest in spate of videotaped executions that the terrorists have posted on social media as they impose their extreme version of "Islamic sharia law" across a swathe of Syria and neighboring Iraq.

In the video, a bearded gunman in combat fatigues stands behind the father, who is dressed in the white robe and chequered headdress typical of the Syrian countryside.

They both face the young black-clad daughter as the gunman addresses her in the classical Arabic of the Koran."The punishment is the result of crimes which you committed under no duress," he says.

"You must accept the punishment of God. Do you accept the punishment of God?"

She nods her head in assent, then turns to her father and asks his forgiveness.He refuses until the assembled IS fighters persuade him to relent.But it makes no difference to his daughter's fate.

She is permitted to speak briefly before the stoning commences. "I say to every woman: preserve your honour ... and I appeal to every father to pay attention to the surroundings your daughter lives in," she says.

Her father then takes a rope, and ties it round his daughter's waist before forcing her to lie down.The IS gunman then orders punishment to begin and the father joins in stoning her to death.

Although ISIS claim imposing "sharia law" in its self-claimed Islamic caliphat, a report by think tank MEMRI – the Middle East Media Research Institution – confirms ethnic sex slavery is taking place on a massive scale in IS-controlled area.

The report states: “During its takeover of large parts of northern Iraq the IS captured many Yazidi villages, and reportedly took many Yazidi women to be sold and used as sex slaves.”

As many as 3,000 Iraqi women have been taken captive in the last month by the terrorist group.