A poster for the forthcoming video shows prisoners wearing orange jumpsuits surrounded by a framework of poles and militants gathered on horses.

It was posted with a warning the bloodthirsty group are planning to reveal a 'new killing style' - in addition to the varying types of executions it already carries out across Iraq and Syria.

ISIS rarely release such videos in full without warning - they instead prefer to drip feed the release in order to gain exposure.

The image surfaced on social media ahead of an impending release of the full execution video, it was claimed, with the word 'soon' written on in Arabic on the poster.

Following the brutal beheading of several captives, the group has carried out many horrific killings - all of which are photographed or recorded and shared online.

In February, Jordanian pilot Muath al-Kaseasbeh was locked inside a metal cage, doused in petrol then burned to death. The video was released in its entirety on the internet.

Meanwhile, stonings have become commonplace in areas controlled by the fanatics as they seek to impose their brutal form of sharia law.

Adultery is a common accusation levelled at those killed by the jihadis - a crime punishable by stoning. In front of gathered crowds, the victims are usually pelted by rocks until they're dead.

Other images and footage released from inside ISIS territory shows men accused of being gay being thrown to their death from tall buildings.

Town square beheadings and the severance of the limbs of those accused of stealing are also so commonplace the spectacles are part of everyday life for citizens trapped under ISIS rule.

The brutal killings are usually directed at those who break the group's strict interpretation of sharia law - this often means LGBT, ethnic groups and other minorities are targeted.

Meanwhile, the first-ever UN Security Council meeting highlighted the 'barbaric treatment' of lesbians, gays, bisexuals and transgender people in territory held by the extremist group.

Jessica Stern, executive director of the International Gay and Lesbian Human Rights Commission, told the council that militant courts in Iraq and Syria claim to have punished homosexuality through stoning, firing squads, beheadings and pushing men off tall buildings.

Fear of Islamic State has fuelled violence by other militias and 'private actors' against LGBT individuals, Ms Stern told the privately-held meeting at UN headquarters in New York.

The Islamic State group is now in control of about a third of Syria and Iraq.

(dailymail.co.uk)