Pittsburgh authorities say they are investigating anti-Semitic pamphlets found in several of the city’s neighborhoods—including Squirrel Hill, where 11 members of the Tree of Life synagogue were gunned down less than two months ago in the deadliest attack on the Jewish community in U.S. history. In a statement Sunday, the Pittsburgh Department of Public Safety said an investigation has been launched into the “hate-filled material.” “Pittsburgh is and will remain stronger than hate,” the statement said. It was not immediately clear how many pamphlets had been disseminated, nor how many neighborhoods were affected. Jewish Federation of Greater Pittsburgh CEO Jeff Finklestein told the Pittsburgh Post-Gazette he’d seen the “anti-Semitic and racist fliers” circulating on Facebook. The pamphlets appeared to be “recruitment information for the Ku Klux Klan,” he said.