Antisemitism in the US is reaching "historic levels" in the wake of violence in Israel and Gaza, FBI Director Christopher Wray has warned.
Speaking to a senate panel on Tuesday, Mr Wray said 60% of all religious-based hate crimes targeted Jewish people.
He added that the figure had likely increased amid anger caused by the ongoing violence in Gaza.
Other countries, including the UK and France, have also warned of a recent major uptick in antisemitic incidents.
"This is a threat that is reaching, in some way, sort of historic levels," Mr Wray told the Senate Homeland Security and Governmental Affairs Committee.
He added that although Jews make up only about 2.4% of the US public, they account for about 60% of all religious-based hate crimes.
"The Jewish community is targeted by terrorists really across the spectrum," he testified.
"This is not a time for panic, but it is a time for vigilance," Mr Wray continued. "We shouldn't stop conducting our daily lives - going to schools, houses of worship, and so forth - but we should be vigilant."
Officials across the US and in other countries have noted a major increase in threats to Jewish people. On Tuesday, New York officials questioned a person after threats were made against Jewish pupils at Cornell University.
On Monday, the Biden administration announced that it was working to combat antisemitism and other hate speech on campuses by increasing communications with local, state and federal authorities.
Offering examples of the threat faced by the Jewish community, Mr Wray cited a man who was arrested in Texas last week for trying to build a bomb and posting about his support for killing Jews, and another man who was arrested in Illinois for killing a six-year-old Muslim boy.
The security chief was appearing before the senate alongside Homeland Security Secretary Alejandro Mayorkas, where the pair offered an analysis of the threat facing the US as the conflict continues.
Mr Wray said that the terror threat to Americans has been "elevated throughout 2023", but has risen again "to a whole other level," after the 7 October Hamas attack.
He added that he was concerned that extremists will "draw inspiration" from the Hamas attack on 7 October.
"The actions of Hamas and its allies will serve as an inspiration the likes of which we haven't seen since ISIS launched its so-called caliphate years ago," he warned senators.
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