While Islamic State is infamous for it’s horrific attacks causing the deaths of untold numbers of innocent people worldwide, their endeavors in the realm of cyberterrorism aren’t as well known. These efforts, while ambitious, are not as effective, according to U.S. authorities. And now, an unlikely cyber-combatant in the fight against ISIS has declared war on them on this front.

The shadowy hacker-activist group Anonymous has announced what they’re calling their biggest operation ever, in the wake of the deadly attacks in Paris. The group released a video on ISIS-affiliated Telegram channels in multiple languages, featuring a Guy Fawkes mask-clad announcer, saying, "We will launch the biggest operation ever against you [ISIS]. Expect massive cyberattacks. War is declared. Get prepared." Anonymous has been calling for collective action against Islamic State since the Charlie Hebdo murders that took place last January.

Last month, the NSA and FBI announced that ISIS-based hackers have been launching cyberattacks against US infrastructure systems, such as the US energy grid. However, the FBI reports that the cyberterrorists have been so far unsuccessful, simply because they aren’t very good at it. The organizations were tight-lipped about any details, but say they are worried that ISIS may simply purchase the tools needed to step up their attacks.

"Strong intent. Thankfully, low capability," explains the FBI’s cyber division section chief John Riggi. "But the concern is that they’ll buy that capability."