Jewish institutions in Vienna, Austria, remained closed on Tuesday after a shooting the night before that left four dead, including a gunman, who was killed by police. The attack took place in the Innere Stadt, Vienna’s old town, an area home to several synagogues, including the historic Stadttempel, near the Danube River. At least 15 people were injured.

Authorities continued to search for possible accomplices throughout the night and day, although police suggested that despite early reports of multiple shooters, the terrorist may have acted alone.

According to Rabbi Jacob Biderman, executive director of Chabad-Lubavitch of Austria, all of the city’s synagogues have been accounted for with no known injuries or loss of life in the Jewish community. “I checked with all five of Vienna’s Chabad Houses, as well as our educational institutions, and thank G‑d, everyone is fine,” Biderman told Chabad.org. “While there is much about this attack that we do not yet know, we are thankful that the Jewish community seems to have been spared from harm and extend our prayers for all those injured.”

In a statement posted to Twitter in German, Oskar Deutsch, president of the Jewish Community in Vienna wrote, “While it remains unclear if the Stadttempel was one of the targets, we’ve confirmed that is that both the synagogue office building at the same address were closed at the time of the shots were fired.”

Austria had 1.3 million Jews before the Holocaust and today has a Jewish population of about 9,000, most of them in the capital of Vienna. Chabad of Austria was established in 1980 and now has 13 institutions throughout Vienna and Salzburg, and serves Jews throughout the country.