Islamic State supporters have apparently declared war against Anonymous which continues its cyber-war against the terror group.

ISIS asked members to unite against the hacking group which removed more than 5500 ISIS-linked Twitter accounts. The extremist group, which uses social media effectively for spreading its propaganda and radicalising youths, depends heavily on popular online platforms like Twitter.

Pro-ISIS Twitter users have been calling Anonymous “idiots” while giving instructions about how to avoid getting hacked by the hacking group, The Australian reports.

ISIS asked members to update their Twitter profile pictures with the French flag with a black shoeprint on it. Another message to the members, written in Arabic, says the Middle Eastern group will strike back against Anonymous.

The hacking group earlier labelled more than 5,500 Twitter accounts with #daeshbags, using a pejorative term for ISIS, and posted those to an online forum. It not only removed the accounts, but also started releasing personal information of suspected extremists.

French members of the hacking group earlier released a video on YouTube and vowed to take revenge for the death of 129 victims in a series of terror attacks in Paris on Friday. The video says ISIS should expect a number of cyber-attacks from Anonymous which is going to undertake its biggest operation till date.

According to News.com.au, Anonymous may keep its promise of a cyber-war against ISIS without facing the constraints of the law. However, Rachel Bryson is not sure of ISIS is really going to declare war against Anonymous.

"I don't know if it is literally declaring virtual war on Anonymous, but it is promising a response - which can easily be declared 'war,' Business Insider quoted the researcher at the Quilliam Foundation as saying. “They are definitely trying to taunt Anonymous with this ... but writing a post is easy, it's doing a strong response that'll be the thing to watch for.”

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