Facebook chief executive Mark Zuckerberg returns after a break to continue testifying at a House Energy and Commerce Committee hearing in April. (Jacquelyn Martin/AP)

Liberal philanthropist George Soros has called on Facebook to initiate an independent, internal investigation of its lobbying and public relations work.

The call comes after the New York Times published a report claiming the company had hired an opposition research firm to discredit critics by linking them to Soros, a frequent target of conservatives and anti-Semitic vitriol from the far right.

“These efforts appear to have been part of a deliberate strategy to distract from the very real accountability problems your company continues to grapple with,” wrote Patrick Gaspard, the president of the Open Society Foundations, a philanthropic organization founded by Soros. Gaspard published the letter Wednesday after publication of the Times report and addressed it to Facebook chief operating officer Sheryl Sandberg. Chief executive Mark Zuckerberg, along with Facebook board members and congressional leadership, were also on the address list.

According to the report, Sandberg oversaw an aggressive lobbying campaign to counter the public backlash against the company, after an onslaught of scandals involving Russian misinformation, privacy violations and the viral spread of hateful messages.

The company adopted a public relations strategy akin to campaign-style opposition research, the report said, in which others were attacked, such as Google and Apple, to deflect blame. Sandberg also wielded her high-ranking position at Facebook to personally appeal to lawmakers in Washington and state attorneys general, the report said, in the hope of curtailing regulations and investigations targeting the social network.

Facebook hired a Republican opposition research firm to discredit activists critical of the social network, according to the report. Some of the efforts linked the activists to Soros, the report said. The firm circulated a document to reporters that “cast Mr. Soros as the unacknowledged force behind what appeared to be a broad anti-Facebook movement,” according to the New York Times, and it “pressed reporters to explore the financial connections between Mr. Soros’s family or philanthropies” and groups critical of Facebook.

The firm cited in the report, Definers Public Affairs, did not immediately respond to a request for comment from The Washington Post.

In a statement Thursday, Facebook told The Post: “It is wrong to suggest that we have ever asked Definers to pay for or write articles on Facebook’s behalf — or to spread misinformation. The relationship with Facebook was well-known by the media — not least because they have on several occasions sent out invitations to hundreds of journalists about important press calls on our behalf.”

Facebook’s stock closed slightly down on Thursday, near its lowest price in a year.

Soros has criticized Facebook’s approach to hate speech and propaganda on its global platform. His spokesman, Michael Vachon, said the Times report raises questions about whether Facebook has used similar “unsavory tactics” against other people who have voiced opposition. “It is alarming that Facebook would engage in these unsavory tactics,” Vachon said Thursday.

“It’s been disappointing to see how [Facebook leaders] have failed to monitor hate and misinformation on Facebook’s platform. To now learn that you are active in promoting these distortions is beyond the pale,” Gaspard said.

Color of Change, a racial justice organization that, according to the report, was targeted in opposition research efforts, said in a statement Thursday that Facebook’s actions were “reprehensible” and “dangerous.”

“Facebook’s response to our campaign, which challenged them to improve their platform and create safe conditions for Black people and other marginalized groups, was to fan the flames of anti-Semitism,” the group said. Among other demands, Color of Change called on Facebook to apologize, to terminate its public policy chief and publish all the opposition research material it compiled about the group and others.