Security authorities in Austria, Germany and Spain received warnings that an Islamist terrorist cell plans to carry out several attacks in Europe on New Year's Eve or Christmas in Cologne, Vienna and Madrid, Haaretz reported on Saturday night, citing Germany's Bild newspaper.
Arrests have already been carried out in Cologne and Madrid, according to the report.
In Vienna, authorities warned of a possible attack on one of the city's symbols, St. Stephen's Cathedral, and said that they have stationed armed policemen at the entrance to the site.
Germany has been on high alert in recent years, following a series of terrorist attacks. The worst such attack took place in December of 2016, when Tunisian terrorist Anis Amri killed 12 people and injured dozens more when he drove a truck into a Christmas market in Berlin.
Tensions have risen since October 7, when Hamas attacked Israel and brutally massacred at least 1,200 people.
The country has seen a sharp rise in antisemitic incidents in the wake of the Israel-Hamas war. In one incident, a synagogue in the German capital of Berlin was firebombed by two assailants. The incident is being investigated as a hate crime.
In late October, police in the western German city of Essen arrested a man who plotted to attack a pro-Israel demonstration.
Last month, a 15-year-old boy was arrested in western Germany on suspicion of planning a possible attack on a Christmas market.
Several days ago, police in Germany, Denmark and the Netherlands arrested seven men they said were planning terror attacks against Jews and Jewish sites.
In Austria, a 16-year-old teenager was arrested earlier this month for allegedly planning to attack a synagogue in the capital of Vienna.