A 32-YEAR-OLD jumping castle salesman from the UK has been confirmed as the new posterboy for Islamic State after appearing in the group’s latest execution video.

Dubbed the new ‘Jihadi John’ — after the British recruit and sick star of several infamous propaganda clips, Mohammed Emwazi, who was killed in an air strike in November — father of four Siddhartha Dhar has now been identified as the man in the video leading the killing of five British ‘spies’ this week.

The confirmation is expected to come as a harrowing shock to Dhar’s family, who overnight spoke of their fears that they recognised the masked man in the footage.

His sister told the UK press, if it turned out to be Dhar “I’ll kill him myself.”

The release of the video immediately sparked a digital manhunt among global security agencies in an effort to identify him.

The British Muslim convert also known as Abu Rumaysah was reportedly able to travel to Syria with his wife and four children despite being out on bail for terror offences.

According to the UK’s Telegraph, Dhar’s family admitted the man featured in the video could be the former jumping castle salesman after both his mother and sister noticed familiarities in the jihadi’s voice.

While his sister Konika Dhar admitted the man “did sound like him,” she said she still couldn’t believe it.

“This is just so shocking for me. I don’t know what the authorities are doing to confirm the identity, but I need to know if it is,” she said.

“He was a very pleasant boy, and I know it may be hard to believe but he still is, and I still believe that he still can be that person.”

Speaking to media gathered outside her North London home, Dhar’s mother said: “I heard the voice, yes, but I don’t know, I’m not sure of the voice. These are the most difficult questions to answer. I just cannot say. I’m not sure within myself whether it is the truth or not.”

THE DIGITAL MANHUNT

Since appearing online just days ago, security agencies had been trying to piece together his identity.

Directing his message to British prime minister David Cameron, Dhar, brandishing a gun, condemned the political leader as a slave to the White House.

“Only an imbecile would dare to wage war against a land where the law of Allah reigns supreme and where the people live under the justice and security of Sharia. Only an imbecile would dare to anger a people who love death the way you love your life.”

Simon Orcsik from Sydney’s Digital Forensic said it’s tough to extract a whole lot of information purely from the visuals of the video, particularly given that its creators are careful not to include anything that gives away their position. But there are things that can be analysed to help form a piece of the puzzle for security officials.

“When you’re working at a federal level, you can throw a lot of resources at it,” he told news.com.au.

The best technique at their disposal is voice recognition which authorities have adopted in an effort to clarify the identity of the masked gunman.

The same technique was used when officials were attempting to identify Mohammed Emwazi, who remained unidentified for nine months after making his first grisly appearance in an IS execution video in 2014 and given the Jihadi John moniker by hostages who likened his accent to one of The Beatles.

Tomorrow's Daily Telegraph front page: "Hunt for the new Jihadi John." pic.twitter.com/tR5SVbzm04 — The Telegraph (@Telegraph) January 3, 2016

WHAT DO WE KNOW ABOUT SIDDARTHA DHAR?

Dhar was raised as a Hindu and went on to run a firm that hired out jumping castles, before marrying his Muslim wife Aisha, at which point he became increasingly more radicalised.

According to reports in the British media, his East London neighbours claimed Dhar’s wife was more devout than him and suggested she may have put him on the path to extremism.

He was believed to be a key member of banned group al-Muhajiroun and thought to be responsible for recruitment “roadshows” that aimed to lure troubled youngsters to Islam.

He had previously been given a platform to spread his views on TV by broadcasters including the BBC, Channel 4 and Al Jazeera. He was also interviewed by CBS News’s 60 Minutes program about radicalisation in the UK, in which he said he was unable to love his mother because she was not a Muslim.

“We believe that whenever the sharia is established, the pure Islamic state maybe in Iraq or Syria, (but) one day the leader will wage jihad and annex Britain into the Islamic state,” he said in an interview at the time.

Dhar was one of six arrested in September 2014 alongside notorious preacher Anjem Choudary on suspicion of belonging to the banned group Al-Muhajiroun.

After skipping bail he boasted that he was able to “breeze through Europe” thanks to Britain’s “shoddy security”.

He later tweeted a snap of himself holding his baby in one hand and a Kalashnikov rifle in the other.

Last year, he was mocked after publishing a Lonely Planet-style brochure painting the “Costa Caliphate” in Syria as an ideal travel destination.

Dhar gushed about the “breathtaking scenery” and “exquisite Mediterranean climate that has all the makings of a plush holiday resort.”

He added: “Snickers, Kit Kat, Twix, Kinder Surprise, Cadburys — yes, yes we have it all.

“If you were worried about leaving behind your local Costa coffee then you will be happy to know that the Caliphate serves some of the best lattes and cappuccinos around. The milk is delightful — creamy and fresh.”

Meanwhile, a toddler in the video, wearing a camouflage outfit and IS headband and dubbed “Jihadi Junior”, has been identified by his family as four-year-old Isa Dare, son of East London Muslim convert Grace ‘Khadija’ Dare who also used social media to brag of her desire to be the first female Briton to kill ISIS hostages from the West.