LOS ANGELES (AP) — U.S. Attorney General Merrick Garland said Thursday that federal officials are investigating a weekend demonstration against the Israel-Hamas war in Gaza that spiraled into violence outside a Los Angeles synagogue.

Fighting between pro-Palestinian demonstrators and counterprotesters erupted Sunday outside the Adas Torah synagogue in the heavily Jewish Pico-Robertson neighborhood and police were called in to break it up. One person was arrested.

Garland said the Justice Department’s Civil Rights Division, the FBI and the U.S. Attorney’s Office for the Central District of California “have been and, as we speak, are collecting evidence on that matter.”

President Joe Biden condemned the violence in a post Monday on social media platform X. “Intimidating Jewish congregants is dangerous, unconscionable, antisemitic, and un-American,” Biden said.

Los Angeles Mayor Karen Bass said the violence that erupted was “abhorrent” and that blocking access to a place of worship was unacceptable. The Los Angeles Police Department on Monday began providing additional patrols in Pico-Robertson and outside houses of worship citywide.

Garland did not comment further on what exactly officials are examining.

But Garland said the “Justice Department will not tolerate criminal acts motivated by anti-Semitic hate,” becoming emotional as he recalled his family’s own history fleeing the pogroms of eastern Europe at the start of the 20th century.

“Let me promise to the Jewish community that this Justice Department will do everything within its power, working with federal partners and state and local partners, to secure the community’s safety,” he said. “And as attorney general, I will do everything in my power to do that.”

Police Commander Steve Lurie said during a security briefing Wednesday evening that authorities were aware that the group of pro-Palestinian demonstrators were coming to target the synagogue, but the “level of anger, vitriol and violence” led to the extra deployment of between 60 and 75 officers to the scene.

The Israel-Hamas war erupted in response to the Oct. 7 assault by Hamas-led militants who killed 1,200 people and took 250 people hostage in southern Israel. The war has killed more than 37,000 Palestinians, according to the Health Ministry in the Hamas-ruled territory. It has sparked a humanitarian crisis and displaced most of the territory’s 2.3 million population.