57% spike in reported anti-Semitic incidents includes bomb threats: ADL A new report cites an increase in bomb threats against Jewish centers.

 -- The reported number of anti-Semitic incidents increased 57 percent in the United States last year, according to a new report from the Anti-Defamation League.

There were a total of 1,986 anti-Semitic incidents in 2017, which included reports of harassment and bomb threats, vandalism and physical assaults, the Audit of Anti-Semitic Incidents report notes.

The ADL, a Jewish civil rights group, released its annual report today that focused only on "real world" incidents rather than online cases, CEO Jonathan Greenblatt said in a call with reporters.

"Sadly, it shows what so many of us felt last year: that there was an anti-Semitic surge in the United States," Greenblatt said.

The 2017 increase marked the largest single-year increase in reported incidents since the ADL started tracking such incidents in 1979.

The majority of the incidents stemmed from harassment, for which there was a 41 percent increase from 2016, and vandalism, for which there was an 86 percent increase, the report states.

There were 163 bomb threats made against Jewish institutions in the first three months of 2017, according to the report.

Neither the ADL report nor Greenblatt definitively connected the spike to a specific source, but the "divisive state of our national discourse" was likely a factor, he noted.

Heidi Beirich, the director of the Intelligence Project at the Southern Poverty Law Center (SPLC), another civil rights group, was more direct in her assessment of the findings, telling ABC News, "I definitely lay some of this at the feet of the Trump administration."

Beirich pointed to "the divisive language that they've used," like President Donald Trump’s response to a violent rally in Charlottesville last year, and his decision to retweet anti-Muslim videos on Twitter as actions that "heightened the kind of ugly rhetoric that used to be kind of kept on the sidelines."

"Language matters,” Beirich said. “The things that are said matter.

Greenblatt did take issue with some of Trump's more controversial retweets, which included some by white supremacists during the campaign.

"Those tweets and rhetoric have emboldened and given encouragement to anti-Semites and bigots," he said.

Jacques Berlinerblau, a professor and the director of the Center for Jewish Civilization at Georgetown University, pointed to ADL findings that moved in tandem with the political winds between 2016 and 2017.

"It's fairly obvious that what shifted in 2017, well, we had a new president and with this new president came a new form of public discourse perhaps not seen from the White House since prior to World War II," Berlinerblau told ABC News.

"This new mode of public discourse was not just restricted to Jews. It concentrated on women, lesbian and gay people, Mexicans, immigrants, African Americans," he said, noting it is "not new in terms of what it is, it is new in terms of where it is coming from."

The Trump administration came under fire in February 2017 for a perceived slow response to the bomb threats made against Jewish institutions, but Trump did call them "horrible" and condemned them in his joint address to Congress.

"The anti-Semitic threats targeting our Jewish community and community centers are horrible and are painful and a very sad reminder of the work that still must be done to root out hate and prejudice and evil," Trump remarked earlier this month.

The 19 reported anti-Semitic assaults was actually down from the 36 assaults reported in 2016, which Greenblatt called the "only bright spot, if you will."

Anti-Semitic incidents were reported in every state, the report notes, though the highest numbers were reported in states with the largest Jewish populations, with New York reporting 380 incidents, which Greenblatt said, was a 90 percent increase from the year before. California reported 268 incidents and New Jersey reported 208.

"Where there are more Jews there tends to be more anti-Semitism," Greenblatt said.

Another reason for the increase in reported incidents could be that people are more concerned about anti-Semitism, he added, and therefore more willing to file reports.