The building and its sidewalks, lampposts and parking lots were found covered Monday with more than a dozen messages, including "Arbeit Macht Frei," ("Work makes you free"), the phrase that greeted new arrivals at the Auschwitz concentration camp during World War II, WRC-TV, Washington, reported.
"I started welling up with tears and tried to conceal it from our 3-year-old," parent Laurie Blumstein told the TV station.
"The remarks about Jews, the German writing, this was done by someone who knew German or was copying it from something," said synagogue member Elaine Senter. "I don't think it was done by kids. It just was too perfect."
Rabbi Ari Sunshine decided to let the messages stand for the time being to allow the community to assess what happened and try to bring unity to the community.
"If we just cover over the words and the symbols and get rid of it in the next hour or two hours, without a chance for people to come together and work at that and symbolically stand together as we remove these words, then a great teaching opportunity will have been lost," the rabbi said.
Montgomery County police are investigating the incident as a possible hate crime.