Yesterday I wrote about Facebook's mass closure of groups used by Arab atheists and secularists following attacks by Muslim activists. Facebook now seems to have had second thoughts about its decision and over the last 24 hours almost all the affected groups have been restored.

This morning, however, the restored groups were reporting fresh attacks by cyber-jihadists.

The attacks mostly take two forms. One is to bombard Facebook with vexatious complaints, accusing the atheist groups of hate speech and other breaches of Facebook's "community standards". (The affected groups insist that they do not allow hate speech and take steps to prevent it.)

A second tactic is to infiltrate the groups and deliberately post offensive material in order to complain about it to Facebook. Sometimes the offensive material is disguised so that group administrators will not immediately spot it. According to Usama al-Binni of the Arab Atheist Network, one of the groups that was blocked and then restored: 

“They post something that looks innocuous – something like pictures of destruction in Syria. They would post maybe 30 pictures, and the pictures that you would see on the outside would be just regular pictures of destruction. But then if you scroll through the pictures when you get to picture 23 or 24 you would start seeing porn.”

Administrators of the atheist/secularist groups have named five Muslim Facebook groups which they say are involved (along with others) in the attacks.

Two of these may have since been closed or suspended by Facebook because they are currently unavailable. One was known in Arabic as "The Islamic Deterrence Organisation". The other, more interestingly, had an Arabic name which was disguised by repeatedly inserting an extraneous letter – presumably so that it would not be picked up by keyword searches. Removing the extraneous letter reveals its name as "The Islamic Army for Targeting Atheists and Crusaders".

Among the groups that are still online, one is called Fariq al-Tahadi, which translates as "the team of challenge" or "the team of provocation". It is a closed group with an enormous membership of 439,876.

The Arabic description of the site proclaims "We are here as the army of Muhammad". It goes on to say that the group targets "anyone who tries to sow division or sedition, or tries to undermine our religion and the unity of our homelands".

A second closed group, also called Fariq al-Tahadi, appears to be a duplicate of the first. It has 498,898 members.

A third closed group, with a name which translates as "Team for Closing Pages that Offend Islam" has 6,241 members.