JERUSALEM — Israeli police say they have arrested a 19-year-old Israeli Jewish man as the primary suspect in a string of bomb threats targeting Jewish community centers in the U.S.

Police spokesman Micky Rosenfeld said Thursday the man's motives are unclear.

Rosenfeld said the man is "the guy who was behind the JCC threats," referring to Jewish community centers in the U.S. that have received dozens of anonymous threats in recent weeks. More than 100 threats were made against JCC centers across the country between January and March including centers in Tenafly, West Orange and Cherry Hill.

It was not immediately clear from reports Thursday morning if those centers, specifically, were among the ones the 19-year-old is accused of threatening.

JCC Association of North America President and CEO Doron Krakow in a statement said they are "gratified by progress in this investigation" and applaud the FBI, Israeli law enforcement and other law enforcement for their efforts. “We are troubled to learn that the individual suspected of making these threats against Jewish Community Centers, which play a central role in the Jewish community, as well as serve as inclusive and welcoming places for all – is reportedly Jewish," Krakow said.

Rabbi Avi Richler, executive director of the Chabad of Gloucester County, told New Jersey 101.5 did not know details about the arrest but said, "a threat is a threat. A threat needs to be taken seriously. I am glad they made an arrest. I am glad they found someone and I hope they can teach a lesson by this arrest to those who are making these threats that even a light threat, perhaps made in jest, will not be taken lightly."

The rabbi was at Gov. Chris Christie's announcement on Tuesday creating a $1 million grant available to non-profit organizations and religions institutions in nine counties for additional security in the wake of the threats.

“Unfortunately, as incidents in the past few weeks have shown, every area of New Jersey is vulnerable to threats and possible attacks, making these additional resources crucial in our efforts to enhance security in certain parts of the state that had not previously received federal security grant funding,” Christie said.

Rosenfeld said the man, from the south of Israel, used advanced technologies to mask the origin of his calls and communications to synagogues, community buildings and public venues. He said the man also made threats in New Zealand and Australia.

He says the investigation was carried out with the help of the FBI and police from other countries.

The Associated Press contributed to this report.

Contact reporter Dan Alexander at Dan.Alexander@townsquaremedia.com

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