An overnight explosion damaged a Jewish school in Amsterdam, though no injuries were reported, prompting an investigation.

Mayor Femke Halsema condemned the blast as a “cowardly act of aggression,” while Dutch Prime Minister Rob Jetten called it “terrible” and vowed stronger protection for the Jewish community.

Police have CCTV footage of the suspect and have scaled up national security measures following a series of attacks on synagogues in the Netherlands, Belgium, and the U.S.

Four men linked to prior incidents in Rotterdam were arrested, and a separate attack in Detroit involved a suspect whose relatives had recently been killed in Israeli strikes on Lebanon, CBS News has reported.

Authorities across Europe and the U.S. have increased security at Jewish institutions in response to the rising wave of antisemitic violence amid the ongoing Middle East conflict.