The Anonymous hacking collective has "declared war" against the terrorist organizations said to be responsible for the shootings of staff at France's satirical Charlie Hebdo magazine, reports The Telegraph.

The threat took the form of a YouTube video, in which a French speaking individual in a Guy Fawkes mask explains why the group is to "declare war on you, the terrorists".

In the video, the masked man says that the hackers will "track down and close all accounts on social networks related to terrorists in order to avenge those who have been killed."

The Washington Times states that the video threat is from a Belgian group of the Anonymous hacking collective.

The video release was followed up with a statement entitled "a message to the enemies of freedom of expression" submitted to Pastebin, in which the hackers offers their sympathies to the families of those killed in the attacks before stating that, "It is our responsibility to react ... Attacking freedom of speech is a direct hit to democracy. Expect a massive reaction from us, because this freedom is what we've been always fighting for."

While no specific websites or accounts are highlighted as being targets for Anonymous, the YouTube video description reads states it is a warning to "al-Qaeda, the Islamic State and other terrorists."

The attacks on Charlie Hebdo last Wednesday left 12 people dead, including eight journalists from the magazine, and Tech Crunch reports that the justice and interior ministers of 12 European countries have put out a joint statement calling for increased digital surveillance in wake of the atrocity.

In the statement, the countries - including the UK, Germany and France argued that given "the increasingly frequent use of the internet to fuel hatred and violence," it is the responsibility of ISPs and governments to "create the conditions of a swift reporting of material that aims to incite hatred and terror and the condition of its removing, where appropriate/possible."