Image copyright Facebook / ابو عزرائيل Image caption One of the pictures of Abu Azrael ("Father of the archangel of death") being shared on Facebook.

The fight against Islamic State in Iraq is raging in Tikrit, where government forces are being helped by dozens of Shia militias. One soldier in particular has gained thousands of fans online - but his story is also a revealing insight into Iran's propaganda machine.

He wields an axe, a sword and a machine gun and his battlefield pranks have become as legendary as his fighting against Islamic State - but who is the man that thousands online have called "father of the archangel of death"?

He's bald, with a prodigious beard, and often pictured with a smile on his face even when carrying his favourite weapons. A Facebook page devoted to his feats has more than 300,000 likes, with the vast majority of his fans inside Iraq itself. And he's been given the terrifying moniker Abu Azrael: "father of the archangel of death."

Of course nothing is quite so simple when it comes to the fight against IS, and basic facts about the Abu Azrael story are difficult to verify.

Image copyright Al-Alam

His real name, according to a report published Tuesday by news agency AFP, is Ayyub Faleh al-Rubaie. He says that he's fought against IS in half a dozen places, but that his experience goes back much further than the current conflict. Rubaie told AFP that he was part of the Mahdi Army - a militia that battled US forces in Iraq. He also says that he fought near Damascus against Syrian rebels trying to unseat President Assad.

In between describing his mercilessness against IS fighters, Rubaie told AFP that he is a father of five. "You see me go to school to drop off my children and I am peaceful. But I show another face to them (IS)," he says. The apparent contrast between his battlefield adventures and his seemingly ordinary background seem to be part of the appeal of his story. Al-Alam, a state owned Arabic-language TV station in Iran, reported that he used to be a physical education teacher at a university in Iraq. Al-Alam also said he's skilled in taekwondo and shooting, according to BBC Monitoring.

The Twitter account @IraqLiveUpdate reports news from the country and they too have featured Abu Azrael - posting a picture of him meeting with Iraq's transport minister. But their version of the story contradicts the idea that Abu Azrael was a university teacher. They told BBC Trending that he's actually an experienced special operations fighter.

Image copyright Twitter Image caption Abu Azrael meets with a top Iraqi politician in this photo posted by @IraqLiveUpdate

No matter what the truth about the details of his life, Abu Azrael's story is significant because of the insight it provides into neighbouring Iran's propaganda machine. The presence of large numbers of Shia fighters like him in Tikrit - part of Iraq's Sunni Muslim heartland - is alarming to many. Some of the fighting forces have alleged links to Iran, and there are worries their presence could destabilise the region even further. One of the Facebook pages most heavily promoting Abu Azrael's photos is devoted to Iranian Revolutionary Guards special forces. The foreign branch of the Iranian Revolutionary Guard - the Quds force - is reportedly involved in the battle in Tikrit.

Image copyright IRGC / Facebook Image caption A Facebook page devoted to the Iranian Revolutionary Guard has posted a series of pictures of Abu Azrael

Abu Azrael himself appears to be a member of the Kata'ib Imam Ali militia. Phillip Smyth, an expert on Shia militias at the University of Maryland and a blogger at Hizballah Cavalcade, says the group was formed last summer and immediately started promoting their star soldier using a sophisticated strategy.

"I've been watching Shia militias on Facebook and social media for years and this fits the model of an organised campaign," he says. "He had his own Facebook profiles and pages, the earliest in late 2014 … they had built up the character quite well, and initial photo releases were shown of him doing heroic or interesting things." The Kata'ib militia has also posted much darker social media content, Smyth says, including severed heads of what they claim are IS fighters.

Most of Abu Azrael's Facebook fans are Iraqis, but Iranians have also taken an intense interest in him, sharing photos and suggesting that his tough appearance belies a kind nature and a good sense of humour. Pictures and a video being shared online show a smiling and waving Abu Azrael riding a bike, supposedly through battle zones. And a popular video shows him taunting IS militants with a "captured" walkie-talkie. One of his followers has even created a cartoon of Abu Azrael pounding a man "into flour" - a punishment he promises to inflict on his battlefield opponents.

Image copyright Facebook

Reporting by Farhad Daneshvar, Gemma Newby and Nader Ibrahim

Blog by Mike Wendling

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