Basil Ramadan, said to be in his 60s, used an AK-47 to gun down a group of militants at a checkpoint in Tikrit, a city northwest of Baghdad currently under ISIS control, before he was shot.

Mr Ramadan's son, Ahmed Basil, 18, was one of eight men executed by ISIS in January, accused of infiltrating the organisation and spying for the Iraqi government.

ISIS released photos from a video of the execution of Ahmed Basil Ramadan and seven others, all said to be police officers, accused of informing on Islamic State for the Iraqi government. 

Entitled 'the Day of Judgement', the photos from the video show eight Iraqi men dressed in orange Guantanamo Bay style jumpsuits. 

Standing behind them are Islamic State's notorious security forces, known for carrying out mass public executions in broad daylight.

Several of the victims, including Mr Ramadan's son, are named in the captions and appear to have been interviewed for the video as they are seen wearing microphones.

In the video, Ahmad Basil Ramadan is accused of giving information on the location of Islamic State soldier houses.

The leader of the group is named as Captain Hossam Salah Bnosh. According to Islamic State media, Bnosh and seven other police officers converted to Sunni Islam and joined Islamic State.

However once they had infiltrated the Islamic State 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 Islamic State. 

Another prisoner wearing a microphone is named as Marwan Habib Said, who reportedly joined Islamic State 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 Islamic State 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 Islamic State fighter draws their pistol and takes aim.

Each prisoner is executed with a single bullet to the head. Afterwards, the security forces pose for a photo. The squadron are shown pointing their pistols at the video camera.

(dailymail.co.uk)