Entitled 'the Day of Judgement', the photos show eight Iraqi men dressed in orange Guantanamo Bay style jumpsuits.
Standing behind them are ISIS's notorious security forces, known for carrying out mass public executions in broad daylight.
Several of the victims are named in the captions and appear to have been interviewed for the video as they are seen wearing microphones.
The leader of the group is named as Captain Hossam Salah Bnosh. According to ISIS media, Bnosh and seven other police officers converted to Sunni Islam and joined the so-called Islamic State
However once they had infiltrated the ISIS security forces, they began to secretly spy for the Iraqi government.
The group are accused of providing intelligence information to the Iraqi government, identifying targets for coalition airstrikes against ISIS.
Ahmad Basil Ramadan, a young bearded Iraqi, was accused of giving information on the location of ISIS soldier houses.
Another prisoner wearing a microphone is named as Marwan Habib Said, who reportedly joined ISIS security forces but was caught giving target information to the Iraqi government.
The photos show how the eight prisoners were blindfolded and frogmarched along the edge of the river, most likely the Euphrates.
Their hands are handcuffed behind their backs and each ISIS fighter appears to be holding their victim's neck as they march to their deaths.
They appear to have been taken to a quiet area away from the city, possibly under a motorway bridge, near the river. Forced to kneel down and unable to see, the prisoners wait as each ISIS fighter draws their pistol and takes aim.
