The speculation is as flimsy as it can be, seemingly based on little more than Dhar’s sister, Konika Dhar, telling the Press Association news service that while she doesn’t think the man in the video is her brother, the voice on the video sounds “a bit like” his.

AD

If it is her brother, she said, she would “kill him myself.”

AD

Shiraz Maher, a respected specialist on Islamic State radicals at Kings College in London, said on Twitter that he is “not at all convinced” that Dhar is the video killer. “New guy doesn’t sound like him and is much too bulky,” Maher tweeted.

On Twitter, people were about evenly divided over whether the masked man on the videotape sounded just like Dhar or nothing at all like him.

Clarissa Ward of CNN tweeted that the voice “sounds just like” Abu Rumaysah, whom she interviewed for "60 Minutes" just before he fled to Syria. “I shivered—it’s his voice,” she tweeted.

Authorities have made no official comment on the identity of the new killer.

AD

The Telegraph newspaper reported Monday morning that a young boy in camouflage gear shown at the end of the video saying “kill the kuffar” (non-believers) is the son of a British woman, Grace “Khadija” Dare from southeast London, who went to Syria in 2012.

AD

If Siddhartha Dhar has taken over from the first Jihadi John, a Kuwait-born Londoner named Mohammed Emwazi, who officials believe was killed by a drone strike in Syria in November, it would be quite a radical turn for the former pharmacy clerk who once dreamed of being a dentist.

Dhar was a well-known nemesis of the British government before he left for Syria. For years, he had been something of a spokesman for Islamic radicalism in Britain, giving many media interviews in which he called for establishing sharia law in the United Kingdom. He demanded that women be completely covered in public, that men be “lashed for fornication” and that hands be cut off for theft.

AD

For a long time, he was regarded essentially as a noisy nuisance much like his mentor, Anjem Choudary, probably the best-known radical Islamic spokesman in Britain.

AD

Dhar was also a childhood friend of Mizanur Rahman, another Choudary protege, whom British and U.S. officials now describe as a charismatic online recruiter for the Islamic State. Rahman had converted Dhar, the London-born son of Indian Hindu immigrants, to Islam when Dhar was 19.

Dhar, along with Choudary and Rahman, was arrested in September 2014 on suspicion of belonging to Islamist groups banned in Britain and for “encouraging terrorism.” Choudary and Rahman face an upcoming trial on related charges.

AD

But Dhar skipped bail and moved with his wife, Aisha, and four children to Syria, representing a trend of entire families moving to live in the Islamic State. A month later, he posed in Raqqa, the Islamic State’s self-styled capital, with his newborn son in one hand and an assault rifle in the other.

AD

Dhar went on to become one of the Islamic State’s most high-profile online personalities. Last May, he was listed as the author of “A Brief Guide to the Islamic State (2015),” an almost comically absurd travel guide comparing Islamic State territory to a “plush holiday resort” with a wide array of chocolates available: “Snickers, Kit Kat, Bounty, Twix, Kinder Surprise, Cadburys – yes, yes we have it all.”

“If you thought London or New York was cosmopolitan then wait until you step foot into the Islamic State,” the guidebook states, with no apparent irony.

AD

Also last year, Dhar was identified as the author of a lengthy defense of Jihadi John, which was reported by the Telegraph. In the article, he said violence committed by the Islamic State is no worse than violence committed by coalition forces fighting it.

AD

"Even though we have been force-fed by the media to believe that the Islamic State is 'barbaric' and 'medieval', if you want to torture an Islamic State soldier, bomb an Islamic State building or perhaps nuke Raqqa, all of a sudden such behavior is deemed perfectly rational," he wrote. "You are not barbaric for wanting this, on the contrary, you are civilized and educated.”

He added: "Yes, violence can be justified -- bombs, bullets, knives, air strikes etc. are needed for the right enemy and we should not be made to feel ashamed about it.”