Has Facebook Chief Executive Mark Zuckerberg turned to cracking the whip and putting company executives who go against him on timeouts?

Zuckerberg might not have gone that far. But according to a report in the Wall Street Journal, the Facebook kingpin has in recent months adopted a new, aggressive management style that has led to the departure of several top company executives — and to friction with Chief Operating Officer Sheryl Sandberg.

Zuckerberg reportedly told Facebook officials during the summer that he was going to “war” in order to fight back against criticism coming from lawmakers, federal regulators and Wall Street in the wake the Cambridge Analytica scandal and other matters affecting the security of Facebook’s platform and slowing new user growth rates. The Journal said that Zuckerberg’s new, harder-edged management style has resulted in the clashes with, and the departures of, executives from several of Facebook’s high-profile acquisitions in recent years, including the co-founders of Instagram and WhatsApp, and one of the co-founders of virtual-reality headset maker Oculus VR.

One executive who remains with Facebook, but has also felt Zuckerberg’s wrath, is Sandberg, the company’s No. 2 executive. According to the Journal, Zuckerberg took Sandberg to task for not addressing Cambridge Analytica quickly enough and clamping down on the use of objectionable and controversial material on the site. The situation between Zuckerberg and Sandberg became so intense that Sandberg reportedly told some of her friends that she thought her job might be at risk.

The report about Zuckerberg’s management style came just days after a New York Times expose that included details about the company hiring Definers Public Affairs, a Republican-backed firm to launch campaigns to discredit some Facebook critics. Sandberg denied knowing that Facebook had hired Definers, and the company cut ties with the firm late last week.

On Friday, several U.S. senators sent a letter to Zuckerberg asking him to answer a slate of questions about what efforts it used to go after its critics, especially in the aftermath of the 2016 presidential election.

Facebook didn’t immediately return a request for comment on the Journal report.