WASHINGTON — Painting a grim picture of Jewish vulnerability in the United States, a top US security official said that the vast majority of funds earmarked to secure non-profits goes to Jewish institutions because their need is most acute.Alejandro Mayorkas, the deputy homeland security secretary, speaking Wednesday to the Orthodox Union’s annual leadership mission to Washington, said rising extremism in the United States and its threat to the Jewish community helped keep him awake nights.He said the threat had shifted in the last year from the relatively small number of Americans who were radicalized overseas, to homegrown extremists whom the Islamic State terrorist group had reached through the Internet. The FBI was tracking more than one thousand suspected extremists across the United States, and they were to be found in all 50 states, he said. “They find great access to a radicalizing Islam” on the web, Mayorkas said of the homegrown extremists. “They find what they believe is purpose and meaning in their life.”"The nonprofit security grants approved by Congress — $20 million this year — 'preeminently' go to the Jewish community,” Mayorkas said.“The need is most acute in the Jewish community because of the ascension of antisemitism and hate crimes we see,” Mayorkas said.In past years, more than 90 percent of the funds have gone to Jewish groups. The FBI reported last year that 57 percent of reported anti-religious hate crimes had an anti-Jewish bias. Mayorkas challenged Jewish leaders to raise awareness about potential threats, to hire better-trained security staff, to add protections at Jewish institutions, to train the community in how to respond to an active shooter, to establish relationships with local police and to increase cyber security. He said hackers could access personal information about Jewish children who are affiliated to Jewish organizations and use it to target them.“This is real,” he said. “This is real. We must treat the imminence” – of an act of terrorism – “as real.”He said his trepidation was in part formed by his upbringing. Mayorkas’ mother is a Romanian Jew who survived the Holocaust and who moved to Cuba after marrying a Cuban Jew. They moved to the United States after the Cuban revolution.Among the things that “keep me up at night,” he said, was the threat to “my community,” the Jewish community, he said.“I come from a tradition of a lack of security instilled in me as a very young person,” he said.He said extremism was rising across the world.“We live in a time of increasing concern, not diminishing concern,” Mayorkas said. “If one takes a look at some of the political leaders gaining ascension across the globe, it does not give me comfort with respect to the Jewish community,” he said, stressing that he was referring to foreign leaders and not domestic politicians.Mayorkas also urged leaders to contact Paul Goldenberg, who heads the Secure Community Network, the security arm of the Jewish Federations of North America, to learn more about how to secure their institutions. Separately, Goldenberg was reappointed Wednesday to the Department of Homeland Security’s advisory council, which consults with Mayorkas and Homeland Security Secretary Jeh Johnson. Goldenberg was first appointed to the council in 2013.