The grandfather of the British child soldier dubbed 'Jihadi John Junior' has accused ISIS of using the four-year-old 'as a shield' and pleaded for his safe return to Britain.

Isa Dare was seen in a sickening new execution video wearing military fatigues and being forced to declare: 'We are going to kill the kaffir (non-believers) over there.'

His mother is Muslim convert Grace 'Khadija' Dare, 24, from Lewisham, South-East London, who had links to the killers of Lee Rigby and fled to Syria with her son three years ago.

Last night, Isa's grandfather Henry Dare, 59, who is also known as Sunday, spoke of his disgust at ISIS's latest publicity stunt.

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Child soldier Isa Dare seen in a sickening new execution video wearing military fatigues and being forced to declare: 'We are going to kill the kaffir (non-believers) over there' while pointing into the distance

In 2014, Dare posted a shocking photograph to her Twitter account of her then four-year-old son Isa, meaning 'Jesus', holding an AK-47 rifle. He bears a remarkable similarity to the child in the latest propaganda video

Jihadi bride: Isa Dare's mother, Grace, who fled to Syria with him three years ago is seen with her husband, ISIS militant Abu Bakr, who is dead

Her father Henry Dare told Channel 4 News that his grandson is 'definitely' the boy in the sick ISIS video. Mr Dare, who is also known as Sunday, has begged his daughter to return to Britain

But he said of Isa: 'He's my grandson. I can't disown him.' He urged his daughter to return to Britain to 'face the music'.

He told Channel 4 she had called him from Syria 'weeks ago', having 'brought shame' on the family.

His daughter had told him she was going to Egypt to study and when he found out she was in Syria, 'I dropped the phone on her because I was annoyed'.

Asked if he thought his grandson had any idea what he was saying in the video, Mr Dare – of Deptford, South-East London – said: 'No – he's a kid.

'He's a minor, he's under five. He's acting under the influence of ISIS guerrillas. He's too young.'

Mr Dare added: 'He's propaganda. They are just using a small boy. They are using him as a shield.'

Mr Dare said he had reported Grace to the police on three occasions before she left for Syria and told them "she's behaving in a very funny way".

He added: 'They told me, "She's free". They said she's above 18.'

Talking about his feelings for his daughter and her family, he said: 'I don't want to have any contact with them.

'They've let me down. I'm totally disappointed. She was a Christian, she was brought up in a Christian way – all of a sudden she decided to become a Muslim.'

Another picture of a youngster posing with a toy gun in front of an ISIS flag in 2014 and thought to be Dare's son, also bears a similarity to the child. It was tweeted by Londoner Umm Khattab, the teenaged widow of an ISIS fighter with the caption: 'Next generation, Bi'ithnillah (God willing)'

Images of Isa look remarkably similar to those of the young boy featured in the video. Dare's father Henry Dare has now confirmed that his grandson is the boy in the ISIS video

He said he last saw his grandson two or three years ago, 'before they went to Syria'.

Of the discovery that he was in the new ISIS video, he told the Mail: 'I was very surprised.'

He then criticised the authorities over their lack of action to bring his grandchildren back to safety, saying: 'The police are of no help – they're doing nothing.'

The video, which shows five men accused of being UK spies being murdered, is being examined by the British security services who are thought to be confident they have already identified both the boy and the masked fanatic who fronted it.

The majority of the footage, which has yet to be independently verified, features the balaclava-wearing man who labels Mr Cameron 'an imbecile' for launching air strikes in Syria, before killing a prisoner. Four other men then kill a prisoner each.

He speaks in a British accent and appears to mimic the style of the Briton known as Jihadi John – real name Mohammed Emwazi – who was killed in a US drone strike in Syria in November.

Yesterday, there were unconfirmed reports that the 'new Jihadi John' could be British Muslim convert Siddhartha Dhar – a former Hindu from North London who became radicalised and changed his name to Abu Rumaysah. A number of experts disputed this identity.

Dare is married to a Swedish Islamic fighter called Abu Bakr, and is reported to be a convert who previously attended a mosque in South London. The couple are pictured with their child in a Channel 4 report in 2013

In the same footage she urges other Muslims to 'stop being so selfish...focusing on your families or studies' and implores them to join her in Syria and join the holy war

The footage shows Dare and another veiled woman going about daily life in Syria. She told reporters she can use a Kalashnikov and would like to fight, but has had to settle for the life of a jihadi's wife

Two years ago, Dare swapped her 'comfortable life' in Britain, where she was known for her dimples and her love of her mother's home cooking, for the horror of Syria, where she has joined the terror group ISIS

BABES IN ARMS: THE YOUNG BRITISH MOTHER VOWING TO BE THE FIRST WOMAN TO KILL WESTERNERS AND HER AK-47 WIELDING TODDLER SON Two years ago, Grace 'Khadijah' Dare swapped her 'comfortable life' in Britain, where she was known for her dimples and her love of her mother's home cooking, for the horror of Syria, where she joined the terror group ISIS. Friends have previously described Dare, from Lewisham, South London, as a bit of a tomboy who enjoyed wearing tight jeans and platforms. She also had braces and dimples and 'was very cute'. Dare liked to watch football on TV as a child, and loved Chinese food and her mother's home cooking. When she was older she went to a local college to study media studies, film studies, psychology and sociology, and was a popular young girl. But it was at the age of 18, that she converted to Islam and began worshipping at the Lewisham Islamic Centre – which has links to both the Woolwich killers of Lee Rigby and radical cleric Abu Hamza. Upon travelling to Syria, Dare lied to her family and told them she was travelling to Egypt to further her studies. She admitted in a Channel 4 report in 2013 that when she began wearing the full face veil in Lewisham people on the street told her to 'go back to her country', to which she replied: 'I was born round the corner'. In the same footage she urges other Muslims to 'stop being so selfish...focusing on your families or studies' and implores them to join her in Syria and join the holy war. Hours after the beheading of American journalist James Foley at the hands of a British jihadist, Dare gloated on social media at his execution and vowed that she would be the first British woman to kill a US soldier. Dare was gleeful that the 'UK must be shaking up' after the execution and from her home in the Syrian scrub she tweeted: 'Any links 4 da execution of da journalist plz. Allahu Akbar. UK must b shaking up haha. I wna b da 1st UK woman 2 kill a UK or US terorrist!' Advertisement

Grace Dare is believed to have been radicalised online, then began attending the Lewisham Islamic Centre, where Fusilier Rigby's murderers Michael Adebolajo and Michael Adebowale are reported to have worshipped.

The mosque has denied they were part of the congregation. Her mother Victoria said she changed her first name to Khadija after she began attending the mosque.

'I still call her our Grace,' said the mother. 'I want her back in my life. She is the only child that I have and the devil took her away.'

Dare, born in London in 1991 of Nigerian descent, went to Syria in around 2012 and married a Swede known as Abu Bakr. He is now dead.

She used social media to gloat about the beheading of American journalist James Foley and said she wanted to be the first British woman to kill an ISIS hostage.

In the 10 minute long propaganda video, one executioner (pictured) described the Prime Minister as an 'imbecile', adding: 'Your children will pay for your deeds'

The terror group's captives (pictured), dressed in orange jumpsuits, were filmed 'confessing' in Arabic to spying for British security service

UNMASKING THE NEW 'JIHADI JOHN': EXPERTS STUDY VOICE AND HANDS Intelligence analysts are expected to employ the same techniques used to successfully unmask and track down Emwazi, including voice analysis and possibly even vein-recognition technology that mapped the executioner's hands. They will also be hunting for clues to confirm the identity of the young English-speaking boy who also appears in the video. The killer in the latest video is most likely be of southeast Asian origin, born in the UK, and from southern England, according to a leading forensic analyst. The voice analyst told The Times that he was likely to have been badly educated due to his stilted style and that fact that his words were spoken as though he were reading from a script. Advertisement

Her mother, also from Lewisham, said of her daughter in a BBC TV documentary last April: 'She loved church. She had a Bible, she read the Bible.

'She would sit and pray and pray and pray.'

Downing Street said the release of the video on Sunday showed the terrorist group was 'under pressure'.

The footage shows five men in orange jumpsuits 'confessing' to taking money in return for filming and photographing sites within Raqqa, the capital of ISIS's self-declared caliphate.

A member of a Raqqa-based group which opposes ISIS told the Radio 4 Today programme that the victims included shopkeepers and businessmen from the town.

The Prime Minister's official spokesman said of the video that 'it reflects the barbarity of this organisation but it is also a propaganda tool. This is a terrorist group we are seeing put under pressure.'

More than 30 UK children have already been made the subject of family court orders over radicalisation fears, Scotland Yard has revealed.

Judges have considered cases involving 12 different families.

Last year, Assistant Commissioner Mark Rowley, the country's most senior terrorism officer, said some children were 'almost babes in arms', with ages ranging from two or three up to 16 or 17.