Quite a lot has happened after Anonymous declared cyber-war on ISIS members last weekend, but now, after a week passed from the Paris attacks, the group is proudly announcing that it managed to track and take down over 20,000 ISIS-related Twitter accounts.

To review last week's timeline, it all started last Friday, November 13, when a group of ISIS terrorists carried out a series of coordinated attacks on various pre-selected targets in Paris.

Enraged by the attack, by Sunday, the hacker collective known as Anonymous announced it would start a war against ISIS terrorists, vowing to hunt down the social media accounts Daesh members used to coordinate attacks, promote Jihadism, or recruit new members.

By Monday, the group announced it successfully managed to take down 3,824 Twitter accounts, a number that grew to 5,500 by Tuesday when it also started releasing names.

On Wednesday, the hackers released a "How to Hack ISIS" guide, to which ISIS members retaliated with a "How to stay safe online" guide. On the same day, ISIS members had their online help desk taken down from Telegram.

A week later...

Now, seven days after the original attacks, in a video released on the group's YouTube channel, the hackers are claiming that they've managed to take down over 20,000 Twitter accounts associated with ISIS activities. They even provide a list of all the names.

"ISIS, we will hunt you and take down your sites, accounts, emails and expose you," warn the hackers. "From now on, there is no safe place for you online. You will be treated like a virus, and we are the cure."

The group's move to take down Twitter and other social media accounts is a controversial one. Many law enforcement and online security professionals claiming it was the wrong thing to do since those profiles could have been used to track ISIS activities instead.