On Tuesday, the leaders of the Senate Select Committee on Intelligence said they may haul company execs in front of the committee to explain Facebook’s revelation that “inauthentic accounts” linked to Russia purchased political messenging ads during the 2016 campaign. “Now that we’ve opened up this avenue of social media, it’s of great interest for us to get a full accounting from everyone who operates in the space if in fact foreign money found its way in to finance any of the efforts on social media,” Sen. Richard Burr (R-N.C.), the committee chairman, told the Wall Street Journal. Sen. Mark Warner (D-Va.) added that he questions “whether Facebook has put near the amount of resources they need into getting us all the facts.”

On September 6, Alex Stamos, Facebook’s chief security officer, revealed in a post that the company had “found approximately $100,000 in ad spending from June of 2015 to May of 2017—associated with roughly 3,000 ads—that was connected to about 470 inauthentic accounts and Pages in violation of our policies.” The company’s analysis “suggests these accounts and Pages were affiliated with one another and likely operated out of Russia.” Facebook has shut down the accounts and “shared our findings with US authorities,” Stamos wrote. But while he said roughly a quarter of the ads were geographically targeted and gave examples of the general subject matter—guns, LGBT issues, etc—Stamos did not reveal where the the ads actually appeared or detail any of their specific content.

Although $100,000 may sound like a lot, The Daily Beast reported that the Russia-linked ads—which it said demonized Hillary Clinton and stirred up controversial election topics such as illegal immigration and Muslim extremism—may have reached up to 70 million people and gotten hundreds of millions of “impressions.” The bogus accounts didn’t just buy ads, the Beast revealed, they also created events pages to organize rallies and urge Americans to protest in the streets.

In a development that jibes with the plot of the latest season of Homeland, a New York Times investigation presented evidence that thousands of fake accounts posing as everyday Americans may have been used to spread anti-Clinton messages on Facebook and also Twitter—a platform that has its own problems with disinformation, as Mother Jones reported in April.

Since the election—if not earlier—it has been clear that Facebook was central to Russia’s efforts to hijack the election. And there have been numerous reports detailing other failings—the rampant use of Facebook as a fake-news platform by profit-seeking Macedonians, for instance, and the company’s tendency to create political echo chambers for legitimate users.