Synagogues in Fairfield County are on high alert Friday following an online threat against Jewish houses of worship in New Jersey.

Federal agents who apprehended that person say he did not have the means or motive to carry out the threat, but that he harbored anger toward Jewish people.

"This moment is new with the threats rising, but at the same time, it’s been present for us as Jews as long as we existed," said Rabbi Michael Friedman, of Temple Israel in Westport. “How do you keep your doors open and be welcoming and inclusive in an age when security has to be paramount and there are real threats out there in the world?"

The Anti-Defamation League says antisemitic incidents are on the rise. There was a 34% increase in antisemitic incidents in the United States last year. It was 42% in Connecticut.

Security measures have significantly increased at synagogues. Rabbi Evan Schultz, of Congregation B'Nai Israel, says he has reassured congregants that everything has been done to keep the building safe during services.

Friday evening is the beginning of Shabbat, which is Judaism's day of rest. Although synagogues across the state are on high alert, many say the way to fight antisemitism is by gathering together and celebrating Jewish traditions.

“We must come together for Shabbat, engage with our tradition, be together in our community every single week. It’s deeply important to us,” he said.

Westport police say they are increasing their police presence. The FBI Office in New Haven tells News 12 it is continuing to combat hate crime incidents while assisting local police departments with their needs.