According to Kronen Zeitung, police raided apartments, houses, businesses and association premises in the provinces of Styria, Carinthia, Vienna and Lower Austria.

The operation targeted people suspected of belonging to or supporting the Palestinian Hamas movement, which is recognized as a terrorist organization in Austria and the Muslim Brotherhood terrorist group (banned in Russia), the news outlet said, citing the prosecutors' office in the southern city of Graz.

"We oppose these criminal, extremist and inhuman organizations with all the firmness and all the capabilities of the rule of law," Austrian Interior Minister Karl Nehammer said, as quoted by the media outlet.

The Graz prosecutor's office said that more than 70 people are under investigation on suspicion of belonging to and supporting Hamas and the Muslim Brotherhood.

A series of gun attacks rocked the Austrian capital on November 2, leaving four people killed and 22 others injured. One of the attackers, a supporter of the Islamic State terror group (banned in Russia), was shot dead by the police.