A further seven charges have been made against unknown suspects, in figures provided by Interior Minister Johanna Mikl-Leitner (ÖVP) following a parliamentary question submitted by Justice spokesman for the Grüne party Albert Steinhauser.
Around 200 sympathisers of the German "anti-Islamisation" group Patriotic Europeans against the Islamisation of the West (PEGIDA) marched through Vienna earlier this year, where they were met by thousands of left wing counter-demonstrators.
It was reported at the time that some PEGIDA demonstrators were seen making Heil Hitler salutes and heard shouting out Nazi slogans, contravening Austria's anti-Nazi Prohibition Act.
Mikl-Leitner confirmed that Heil Hitler salutes were made at the rally, although no arrests have been made yet. The answer to the parliamentary question also indicated that despite the salutes, the rally was not shut down by police and only ended when PEGIDA leaders called it off at 19:26.
The information has led to strong criticism of the police from Steinhauser, who said: "The answer to the parliamentary question suggests the Vienna police completely failed to intervene in violations of the Prohibition Act that took place at the PEGIDA demonstration."
Also criticising the authorities for not acting when counter-demonstrators were attacked during the event, Steinhauser added that is is obvious that "the Vienna police mainly see their opponents as the anti-fascist demonstrators and have a laissez-faire attitude towards the Nazi manifestations."
He said: "It is a shame that for the first time in a long while in Vienna the Nazis could be open under the eyes of the police and be provocative and go unhindered in Vienna's streets."
Following the announcement of another PEGIDA demonstration planned for this Sunday in Vienna's Resselpark, Steinhauser appealed to the Viennese police leadership to guarantee "that violations of the prohibition law are punished consistently".
PEGIDA demonstrations in Germany have attracted much bigger crowds than those seen in Vienna, with as many as 25,000 supporters turning out in German cities last year.