In response to a Thursday night segment in which a Fox News host seemingly peddled an anti-Semitic trope about Jewish billionaire Michael Bloomberg, Anti-Defamation League CEO Jonathan Greenblatt sent a letter to the network’s chief expressing how “deeply disturbed” he was that the host played into “deep seated anti-Semitic canards.”

On Thursday night’s broadcast of The Ingraham Angle, Raymond Arroyo—filling in for regular host Laura Ingraham—dedicated a segment to Bloomberg’s support of former Vice President Joe Biden’s presidential campaign now that the ex-New York mayor has ended his own presidential run.

While an on-air graphic blared “Bloomberg’s New Job: Biden Puppet Master,” Arroyo stated: “Joe Biden won’t actually be in charge of the things if he is elected president. He will be a geriatric Pinocchio whose strings will be pulled by the politicians, activists, or donors currently propping him up. That includes big donor Mike Bloomberg.”

The Fox host went on to say that this meant “Mike Bloomberg is going to have more power than any ordinary American will in a Biden administration.”

Greenblatt took to Twitter on Friday afternoon to share his letter to Fox News CEO Suzanne Scott while saying it was “disturbing” that Arroyo labeled Bloomberg a “Biden Puppet Master,” adding that the “anti-Semitic trope” echoes “rhetoric from white supremacists” and never should have been aired.

“This charge, and the comments that followed about Bloomberg’s wealth and power, play into deep seated anti-Semitic canards about Jewish power and money,” Greenblatt wrote in his letter to Scott. “The use of the term ‘puppet master’ specifically conjures up longstanding anti-Semitic tropes about Jewish power and the notion of the Jewish puppeteer has figured in anti-Semitic imagery throughout modern history.”

He further noted that while it is “fair game to be critical of candidates and their positions,” parroting “rhetoric employed by white supremacists and other anti-Semites” when speaking about Bloomberg and Democratic presidential candidate Sen. Bernie Sanders (I-VT), who is also Jewish, “unfortunately fits into [a] pattern at Fox News this election season.”

“Even if no anti-Semitic insinuation is intended, casting a Jewish individual as a puppet master who manipulates national events for malign purposes has the effect of mainstreaming anti-Semitic tropes and giving support, however unwitting, to bona fide anti-Semites and extremists who disseminate these ideas knowingly and with malice,” Greenblatt added.

Greenblatt also pointed out that this isn’t the first time that the organization has contacted the network voicing concern about anti-Semitic references made by guests or hosts on the network.

Back in November last year, he called on the network to no longer book frequent guest Joe diGenova after he promoted an anti-Semitic conspiracy theory about Jewish philanthropist George Soros on Fox Business Network’s Lou Dobbs Tonight. After diGenova returned to Fox airwaves a month later, Greenblatt called the return “disturbing” and said it showed Fox’s lack of “remorse” on the subject. At the time, the ADL also confirmed to The Daily Beast that no one from Fox had responded to Greenblatt’s letter.

Fox News has been contacted for comment on Arroyo’s segment and Greenblatt’s letter.