A new video has emerged apparently showing teenagers leading IS captives to their deaths.

Independent.ie reports that the video, posted on social media this evening, shows Islamic State fighters cutting off the heads of eight men.

The victims, said to be Shia Muslims, are believed to have been beheaded in the central Syrian province of Hama.

They have their hands tied behind their backs and are dressed in bright orange uniforms.

A group of teenage boys is seen leading them through a field before each handing a knife to IS fighters who carry out the apparent murders.

The London-based Syrian Observatory for Human Rights - who say the latest video is authentic, according to Associated Press - reports that they documented the executions of 61 people by Islamic State during the ninth month of the declaration of its own 'Caliphate State', between 28th of February and 28th of March this year.

"SOHR believes that the number of people executed by IS in the last nine months is bigger that the number documented by it because there are hundreds of detainees and missing people inside IS jails," the organisation says.