Some 900 police were involved in the raids, which took place in Vienna, Graz and Linz. They follow a two-year investigation into several people suspected of recruiting young people to fight in Syria.

Media reports said a Vienna-based Bosnian-Serb preacher, who was the main suspect, was among those arrested in the raids which began at 4:00am.

See our special feature Profile of a Jihadist

Police also seized "terrorist propaganda," files, a set of brass-knuckles and sums of money in various homes, said prosecutors in Graz, who were coordinating the operation.

Beyond recruiting fighters, the Kronen Zeitung newspaper said that the suspects were investigated for helping to finance the Islamic State group.

Some 150 people have so far left Austria to join jihadists in Syria and Iraq, or have been stopped while trying to do so, according to the interior ministry.

One case which got a lot of publicity in Austria was that of two teenage girls who left for Syria in April, telling their parents that they wanted to "fight for Islam" there.

Vienna 'hub of global jihad'

Vienna is considered by counter-terrorism experts such as John R. Schindler to be a hub of global jihad.  In August, nine Chechens who were planning to wage jihad with Isis in Syria were arrested by Austrian police, and are awaiting trial. 

Austria's Federal Office for the Protection of the Constitution and Counterterrorism (Bundesamt für Verfassungsschutz und Terrorismusbekämpfung) warned in June over the threats faced by the country, saying:

"Religiously motivated extremism and terrorism – above all of Islamic character – as well as Salafi-jihadi groups continue to present a great potential threat…The number of young radicalized followers of violent Salafism continues to rise."

"In this context, the conflict in Syria is of urgent relevance for Austria, since systematic efforts are being made within [Austria] to radicalize and recruit people for the war in Syria…The conflict in Syria has become very popular among violent extremist Salafis."

"The spectrum of recruits to the conflict in Syria is broadly ethnically diverse. The motivation, however, seems to be uniformly jihadi."

Possible Bosnian Connection?

Benjamin Weinthal, European affairs reporter for the Jerusalem Post, identified at least three separate jihadist movements operating in Austria.  One of those has strong links to Bosnia, and is allegedly funded by Iranian officials.

The raids may be linked to police raids across Bosnia-Herzegovina on November 13 as part of Operation Damascus, in which Bosnian authorities arrested eleven Islamist radicals suspected of supporting jihad and terrorism in Syria and Iraq.

The arrests in Bosnia were made because the Salafi-backed Islamist group was allegedly actively recruiting jihadists to fight in Syria and Iraq, were gathering weapons and explosives, and were financing further terrorist operations.