IG/GETTY IS captive on website

FREE now and never miss the top politics stories again. SUBSCRIBE Invalid email Sign up fornow and never miss the top politics stories again. We will use your email address only for sending you newsletters. Please see our Privacy Notice for details of your data protection rights.

The terrified fanatics were photographed with their hands cuffed behind their back with the message: “Kill him or let him go?” Members of the public were then given an hour to vote. Most of those taking part voted to execute the ISIS prisoners and grisly photos - which have since been removed by Instagram - are later added showing them dead. A guerrilla group called Iraqiswat is behind the chilling new tactic as they seek to match the savagery shown by ISIS in Iraq and Syria.

IG Message on site

Photos seen by the Sunday Express show a bloodied, long-haired man, said to be an IS fighter, awaiting his fate. A message from Iraqiswat, which has a skull as its emblem, later confirms: “As you wish my followers. We will kill him.” Another image is then uploaded showing him dead. Experts from the Henry Jackson Society believe the photos are genuine and appear to be from a Shia militia group that includes former members of the Iraqi Special Forces. Research fellow Kyle Orton said: “I think this is probably credible. While this is an official uniform, this is almost certainly from an Iranian proxy militia.

GETTY It is believed the Shia militia group includes former members of the Iraqi Special Forces

“I have not seen them asking for a vote on people’s fate before and there is no guarantee this guy they have is an IS member. The militias treat any military-age male who remained under IS rule as a collaborator. “But atrocities by militia-infiltrated security forces or militias in official uniforms, as is often really the case now, have been really common, as has disseminating the pictures and videos. The messages are: ‘We are tough enough to face IS,’ which is a message to their own Shia constituency and also designed to terrorise Sunnis generally so they will stop rebelling against the Iraqi government.” Instagram confirmed the content has since been taken down. A spokeswoman said: "This content violates our community guidelines and was removed as soon as we were made aware of it."

GETTY US officials said last night that about 180 IS fighters were killed in air strikes

Atrocities by militia-infiltrated security forces or militias in official uniforms have been really common Kyle Orton