Among bearded extremists, the mantra "convert or die" has recently experienced something of a renaissance, proving equally popular among fans of the Duck and Rashidun dynasties. So Christian evangelists were understandably excited this week when news came out that the brother of ISIS leader Abu Bakr al-Baghdadi had supposedly chosen the cross over the sword.

According to World News Daily Report, Abu's brother Mohammed Bakr al-Baghdadi converted to Christianity earlier this month, leading ISIS' self-styled caliph to state, "He is no more my brother then [sic] the miscreant American pigs we slay everyday." This week, the story went viral, earning praise from believers across the Internet.

By Tuesday, a number of Christian, conservative and anti-Islam blogs had picked up the article, as well as independent news agency AINA, whose reports on the persecution of the Middle East's Christian minority have been a favorite of Fox News. Unfortunately for them, the story is completely false.

In reality, World News Daily Report is just one of many terrible faux-satire sites devoted to polluting your Facebook feed, previously appearing on Antiviral for articles like "Woman Arrested for Calling Her Ex-Boyfriend 77,000 Times in a Week."

The most obvious problem with their story is the brother's reported name of "Mohammed Bakr al-Baghdadi," given that "Abu Bakr al-Baghdadi" is an assumed nom de guerre unrelated to the ISIS leader's birth name. Additionally, a photo supposedly depicting the brothers "at happier times" actually comes from a video of 9/11 hijackers Mohammed Atta and Ziad Jarrah.

But despite being totally bogus, the story's ISIS-like advance shows little sign of slowing down. As one of the article's thousands of sharers noted with confidence, "A number of sources are reporting this."

[Image via YouTube]

Antiviral is a new blog devoted to debunking online hoaxes. Follow us on Facebook and Twitter.