Over the weekend, Alex Stamos, Facebook’s former security chief, wrote his own account of a run-in with Facebook COO Sheryl Sandberg, published by the Washington Post.

In it, he confirms a story of how, when and why she yelled at him after he told Facebook’s board that the Russians had used the social network to meddle in the 2016 election.

He also has some blistering criticism for how Facebook – and everyone else – handled Russian interference.

“Yup, Sheryl Sandberg yelled at me,” Alex Stamos wrote in an editorial for the Washington Post on Saturday.

Stamos is Facebook’s former security chief at the center of a blistering New York Times exposé published last week on how Facebook’s leadership dealt with Russian election interference on its platform.

The story reported that senior leadership tried to downplay and deflect the mounting crises, and revealed details that Facebook hired an opposition research firm to attack its critics, with some of those attacks having anti-Semitic overtones.

Sandberg and Zuckerberg have been playing defense ever since. In a Facebook post, Sandberg again admitted that she and CEO Mark Zuckerberg were “too slow” in dealing with Russian election propaganda on Facebook but she wrote, “to suggest that we weren’t interested in knowing the truth, or we wanted to hide what we knew, or that we tried to prevent investigations, is simply untrue.”

So on Saturday, one of the men in the middle of it all, Stamos, went public with his own side of the story.

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He confirmed that he and his team began digging into Russian activity on Facebook without the direct consent of Sandberg or Zuckerberg.

He confirmed that during that initial investigation, Stamos grew alarmed. “Combing through billions of accounts, my colleagues and I had discovered a web of fake personae that we could confidently tie to Russia,” he wrote in the editorial.

Foto: Alex Stamos, Facebook’s former chief security officer.sourceGetty

When he reported his findings to Zuckerberg and Sandberg, they asked him to brief the board. But that meeting with the board was not consoling. He told “the difficult truth,” he described, warning that Russian abuse of Facebook was widespread and that they didn’t even know how bad it was.

Board members proceeded to grill Sandberg and Zuck and when the meeting was over, a furious Sandberg accused Stamos of throwing her and Zuck under the bus, the NYTimes reported.

Stamos basically confirmed that, too, by writing that “Sheryl – as reported in this past week’s New York Times investigation – felt blindsided.” He said that after yelling at him, she later apologized.

But Stamos went on to accuse Facebook of not coming clean about how bad Russian interference was on their social media site, even after they sent a report to special counsel Robert Mueller about it. Mueller is currently investigating Russian election interference.

After the election “Facebook stuck to a public-communications strategy of minimization and denial,” Stamos wrote.

After holding Facebook’s feet to the fire, Stamos then went on to wag his finger at everyone else: US intelligence, lawmakers, major US outlets, too. All them played their parts and rewarding the Russians for their hacking Democrats’s emails and churning out propaganda.

Stamos also has a stark warning that the 2020 presidential election is already looking like its going to get ugly. It’s likely that the Russians are rubbing their hands together and plotting.

If Facebook has really learned its lesson or not, he doesn’t say. But he calls for everyone from our nation’s spies to our lawmakers to the media to lawmakers to change their behavior and be wary.

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