Facebook has been accused of putting thousands of Islamic State (IS) supporters in contact with one another via the social networking giant's "suggested friends" tool, according to a media report.

The Mark Zuckerburg-led company is facing a severe crisis of credibility ever since the news broke out that it improperly shared personal data of its about 87 million users, mostly in the US, with the UK-based political consulting firm Cambridge Analytica, which used it for political purposes.

In a study to be published later this month by the Counter Extremism Project (CEP), an American non-profit organisation, researchers studied the online activities of 1,000 ISIS supporters in 96 countries and observed that radical Islamists were routinely introduced to each other.

It sets out to reveal the extent to which the social media algorithm has helped the ISIS terrorist network.

Critics say that the feature, designed to match Facebook users based on common interests, actively helps terrorists to regroup and build networks. Many of the extremists were recommended to the CEP's own researchers as friends after they viewed some of the extremist profiles.

Robert Postings, of the CEP, told 'The Sunday Telegraph': "Facebook, in its desire to connect as many people as possible, has inadvertently created a system which helps connect extremists and terrorists".

After introductions are made, he said, extremists can quickly radicalise those who had been only curious.

In one case, a non-Muslim in New York was radicalised in six months after accepting a friend request from an ISIS supporter, the study claims.

The CEP said its research had "laid bare" Facebook's inability or unwillingness to address extremist content.

Facebook says it has invested in artificial intelligence and human moderators to identify and remove extremist content.

"We work aggressively to ensure that we do not have terrorists using the site… But there is no easy technical fix to fight online extremism," a spokesperson for Facebook said.