After backing off their initial claims that a fire in this Swiss city's largest synagogue was set deliberately, Geneva police are saying they are unsure of the cause and are still investigating. The blaze in the early morning of May 24 seriously damaged the interior of the Hekhal Haness Synagogue, police spokesman Philippe Cosandey told JTA. Forensic specialists were deployed over the weekend to help determine the cause. A sniffer dog searched for traces of flame accelerants that might indicate arson, and a fuse box was being analyzed to see whether an electrical fault was to blame. Police told JTA on Monday that the probe could take another several days. "So we wait with patience but high tension for the results of the police investigation," said Ron Aufseesser, president of the Geneva Jewish community. The fire blew out windows and destroyed stairs and books. Other parts of the synagogue, located in the residential area of Malangou, were severely damaged by the water used to extinguish the flames. Despite the fire, "life in our community never stopped," said the synagogue's spiritual leader, Rabbi Eliyahu Elkarif. He noted that while community members are still reeling from the shock, prayer services were moved to big tents and 400 people attended a wedding on Sunday. Hekhal Haness, built in the early 1970s, has 1,200 members, mostly Sephardim. Among its founders is Nessim Gaon, chairman of the World Sephardi Federation. It is one of six synagogues in Geneva. Reports of possible arson in a fire coming on the second day of the holiday of Shavuot raised the specter of anti-Semitic vandalism. While police backed off on calling the blaze a case of arson, Gaon's wife, Renee, said "I am certain that it is a criminal act." She stressed in a telephone interview Sunday with JTA, however, that this was strictly her opinion. "We are all shocked," Gaon added. "We are are grateful that the Torah scrolls and other holy items could be saved," she said. "It was good to see how the fire workers and police officers were personally committed to rescuing the cultural assets holy to us." Gaon promised the synagogue would be restored by Rosh Hashanah. She said the synagogue is insured but if additional money is needed, "my husband is ready to pay the rest." Samuel Althof, a spokesman for Children of the Holocaust, which monitors anti-Semitic acts in Switzerland on behalf of the Federation of Swiss Jewish Communities, said, "I don't think anything like this has ever happened in Switzerland, at least as long as I can remember." But there have been incidents of anti-Semitism in Switzerland, including graffiti scrawled on a Geneva synagogue last year. A synagogue and a Jewish-owned clothing store were set aflame two years ago in the Italian-speaking city of Lugano in what police initially described as arson. Authorities later ruled that the attacks were not anti-Semitic - a decision that was criticized by Jewish groups. In June 2001, the head of an Israel yeshiva visiting Switzerland was murdered on a busy Zurich street during the day. Police never found the killer of Rabbi Abraham Gruenbaun. In a Gallup Poll published earlier this year, nearly half the Swiss respondents had anti-Semitic feelings. Observers said the debate on the Swiss role during and after World War II, the critical stance of the Swiss government toward Israel and the recent turbulence at the World Jewish Congress, which generated considerable press here, has contributed to anti-Jewish feelings among the Swiss population.