International groups that have been declared terrorist organizations in the West, such as al-Qaeda, Hamas and Hezbollah, have shifted their recruitment to social networks like Facebook and Twitter to attract members across borders and gather intelligence, according to a new study.

"Today, about 90 per cent of organized terrorism on the internet is being carried out through social media. By using these tools, the organizations are able to be active in recruiting new friends without geographical limitations," said Gabriel Weimann, of the University of Haifa.

"The social media is enabling the terror organizations to take initiatives by making "friend" requests, uploading video clips and the like and they no longer have to make do with the passive tools available on regular websites."

The findings are based on Weimann's decade-long study of the encoded and public internet sites of these international organizations and groups that support them, as well as forums, video clips and snippets relating to global terrorism on various arenas such as Facebook, Twitter, chat rooms, YouTube and Myspace, among others.

Aside from recruitment, Facebook is being used by these organizations to gather military and political intelligence, Weimann said.

"Many users don't even bother finding out who they are confirming as 'friend' and to whom they are providing access to a large amount of information on their personal life. The terrorists themselves, in parallel, are able to create false profiles that enable them to get into highly visible groups," he said.

For example, a statement from Lebanon has stated that Hezbollah is searching for material on the Israeli army's Facebook activity. Countries such as the U.S., Canada and the U.K. have instructed their military personnel to remove personal information from Facebook in case al-Qaeda is monitoring it, said Weimann.

These groups are also openly using social media as a platform to share "professional" information, he added, pointing to an exchange found on the open, non-coded forum belonging to Hamas's military wing, the Izz ad-Din al-Qassam Brigades: "I have a kilogram of acetone. I want to know how to make an explosive with it to blow up a military jeep." Another member promptly provided the instructions.

"The most advanced of Western communication technology is, paradoxically, what the terror organizations are now using to fight the West," Weimann said.