Facebook’s Chief Operating Officer Sheryl Sandberg was directly involved in efforts to research liberal philanthropic billionaire George Soros, The New York Times reported.

According to three people with knowledge of the matter who spoke to the Times, Sandberg asked Facebook’s communications staff via email to look into Soros’s finances after he called Facebook and Google a “menace” to society at the World Economic Forum. Sandberg reportedly wanted to know whether Soros stood to benefit financially from attacks on the tech mammoths.

Not long after, Facebook hired a public relations firm that disseminated information to reporters about Soros’s financial backing of groups critical of the social media giant. After a Times report revealed Facebook’s payments to the Republican-backed firm, Definers Public Affairs, the company was criticized for propagating anti-Semitism.

In an interview with CNN earlier this month, Zuckerberg admitted he regretted the attacks.