After declaring “cyber war” on Isis this weekend with a cautionary video condemning Friday's Paris attacks, Anonymous have already made their first move. The ‘hacktivist’ group has apparently had 900 Twitter accounts associated with the militant group shut down by posting their details on Pastebin – alongside a message for the terrorist group to “expect them”.

“Operation ISIS Continues,” they wrote on the document. “We Are: Muslims, Christians, Jews... We come from all races, countries, religions, and ethnicity. UNITED AS ONE, DIVIDED BY ZERO... ISIS: We will hunt you, take down your sites, accounts, emails, and expose you. From now on, (there will be) no safe place for you online. You will be treated like a virus, and we are the cure.”

This attack is similar to their earlier dox this month on the Klu Klux Klan – only this time, given Isis's heavy reliance on social media, it feels a lot more significant. In fact, the terrorist group has already begun to prepare by attempting to spread a list of instructions that will help its supporters defend against the attacks.

Spread via social media site Telegram, an Isis representative wrote out a guide to prevent being hacked. “The #Anonymous hackers threatened in new video release that they will carry out a major hack operation on the Islamic state (idiots). What they gonna hack?” they wrote, before swiftly defeating that point to list an emergency five-step plan.

However, although it may now seem like Anonymous is making light progress, one cyber security expert claims these attacks may be counter-productive. “To close those accounts is to leave police deaf and blind around some matters,” Olivier Laurelli explained to AFP. “It is important to know that one account is in France, another in Syria or in Iraq.”

“If you see that someone who is connected to the attacks has a link to someone else, it's important for police. Twitter has been quick to close down a large number of accounts but I don't know if it's a good idea.”

Anonymous began the cyber attacks after Isis claimed responsibility for the deaths of 129 people in Paris last Friday.