In a meeting closed to the media, community leaders and elected officials say they discussed the four acts of hate in Bergen County.
Overnight Wednesday, Rabbi Nosson Schuman's home in Rutherford's Congregation Beth -El was targeted.
Someone tossed a Molotov cocktail through his bedroom window.
He and eight members of his family were inside the home at the time..
In an Eyewitness News interview, the man in charge of the FBI's Newark division said the unexploded firebombs recovered from a second-story roof could be crucial to solving the case.
"With an unexploded device there's a greater opportunity to look at how the device was created, to look at the type of accelerant that was used," Agent Ward explained.
In addition to what happened in Rutherford, in the last month there have been incidents of hate in Maywood, Hackensack and Paramus, leaving the Jewish community on edge.
Federal ATF agents say the unexploded devices are a potential treasure trove, but there were no surveillance cameras, so there is no video of the attack.
Investigators are intrigued that larger congregations have not been targeted.
"One of the investigative theories is that they are possibly looking at some of these smaller venues because there is less security and because there is a greater chance of being successful, and then getting away," Ward said.
"I'll feel relieved when they catch the people or person's who have done this," said Michelle Silverman, of Glen Rock Jewish Center.
Rabbi Schuman was in the room as well.
His family is now under police protection..
"There's an expression lightening doesn't strike twice. Sometimes it does and the fear lives within me, I'm worried," Rabbi Schuman said.
Etzion Neuer of the Anti-Defamation League, which has offered a $2,500 award for the arrest and conviction of a suspect, said they were very concerned that there had been four bias incidents in such a short period of time.
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