Austrian police arrested 13 people and raided homes, prayer rooms and mosques around the country early Friday in a mass operation targeting suspected jihad recruiters, prosecutors said.
The operation in Vienna and the cities of Graz and Linz was reportedly one of the biggest ever for the country, involving some 900 police officers.
It followed a two-year investigation into several people suspected of recruiting young people to fight in Syria, the prosecutors said.
Media reports said a Vienna-based Serbian preacher, who was the main suspect, was among those arrested in the raids which began at 4:00am (0300GMT).
Police also seized “terrorist propaganda,” computer files and money in various homes, said prosecutors in Graz, who were coordinating the operation.
Beyond recruiting fighters, the daily Kronen Zeitung said that the suspects were under investigation for helping to finance the Islamic State group.
The operation “confirms our clear message to all jihadists in Austria: you are not safe here,” Interior Minister Johanna Mikl-Leitner said, praising the dawn operation.
A press conference was scheduled for later Friday.
Austria, a majority Catholic country, has seen dozens of its citizens join the jihadist cause in Syria or Iraq, sparking concerns on the national security threat posed by those who returning from the war-ravaged countries.
Some 150 people have so far travelled to Syria and Iraq to fight alongside jihadists, or have been stopped while trying to do so, according to the interior ministry.
The case of two Austrian teenage girls who left for Syria in April, telling their parents that they wanted to “fight for Islam” there, especially grabbed headlines here.
According to the interior ministry, most of the recruits have an immigrant background from the former Yugoslavia or Chechnya.
About 60 are believed to have returned home from Syria or Iraq, and 30 killed in the fighting.
The government has proposed a package of measures aimed at preventing its citizens from joining the jihad cause.
They include stringent controls of minors traveling abroad, and a ban on symbols linked to the IS group, Al Qaeda and other similar organizations. Citizens with dual nationalities who have fought for a terror group abroad would also have their Austrian citizenship revoked.
The package of measures goes to a parliamentary vote in December.