The number of anti-Semitic incidents that occurred last year in Austria increased by more than 80 percent from 2014, the Austrian Forum Against Anti-Semitism said on Wednesday.

The Austrian organization, which has been monitoring anti-Semitic incidents since 2003, said that 465 such incidents were recorded last year, among them 200 relating to Internet postings. The number of anti-Jewish Internet posts that could potentially be classified as criminal doubled from 2014 to 2015, according to an Austrian Interior Ministry spokesman, the Jerusalem Post reported.

“There is an increasing concern in our community that—if the proportion of Muslims in Austria continues to rise due to immigration, due to the refugees—this could become problematic for us,” Jewish Communities of Austria Secretary General Raimund Fastenbauer said.

There are 15,000 Jews living in Austria.