Representatives of the U.S. Department of Homeland Security are in Chicago to address security at Jewish institutions.

They arrived Sunday and are working closely with the Chicago Jewish federation, according to Paul Goldenberg, national director of the Secure Community Network (SCN), a security agency that is the product of the Jewish Federations of North America and the Conference of Presidents of Major American Jewish Organizations.

This week, senior Homeland Security leadership will begin a series of conference calls with Jewish leaders across the country focusing on increased security concerns after last Friday’s bomb threat in which two packages of explosives mailed from Yemen and allegedly targeting Jewish institutions in Chicago were intercepted. One was intercepted at a FedEx way station in the United Arab Emirates, and one in London.

Hidden inside printer cartridges, the explosives were powerful enough to bring down a plane. Officials are still trying to determine the intended targets  – the planes carrying the bombs or the institutions to which they were mailed.

“SCN is monitoring the situation on a national basis,” said Goldenberg.