WASHINGTON (TIP): Rabbi Joshua Bolton of the University of Pennsylvania’s Hillel center surveys damaged headstones at Mount Carmel Cemetery on Feb. 27, 2017, in Philadelphia.

Jewish centers and schools across the nation coped with another wave of bomb threats Monday as officials in Philadelphia made plans to repair and restore hundreds of vandalized headstones at a Jewish cemetery.

Jewish Community Centers and day schools in at least a dozen states received threats, according to the JCC Association of North America. No bombs were found. All 21 buildings 13 community centers and eight schools were cleared by Monday afternoon and had resumed normal operations, the association said.

It was the fifth round of bomb threats against Jewish institutions since January, prompting outrage and exasperation among Jewish leaders as well as calls for an aggressive federal response to put a stop to it.

“The Justice Department, Homeland Security, the FBI, and the White House, alongside Congress and local officials, must speak out and speak out forcefully against this scourge of anti-Semitism impacting communities across the country,” said David Posner, an official with JCC Association of North America. “Members of our community must see swift and concerted action from federal officials to identify and capture the perpetrator or perpetrators who are trying to instill anxiety and fear in our communities.”

The FBI and the Justice Department’s Civil Rights Division are probing the threats. (AP)