WASHINGTON — Under growing pressure from Congress and the public to reveal more about the spread of covert Russian propaganda on Facebook, the company said on Thursday that it was turning over more than 3,000 Russia-linked ads to Congressional committees investigating the Kremlin’s influence operation during the 2016 presidential campaign.
“I care deeply about the democratic process and protecting its integrity,” Facebook’s chief executive, Mark Zuckerberg, said during an appearance on Facebook Live, the company’s video service. He added that he did not want anyone “to use our tools to undermine democracy.”
“That’s not what we stand for,” he said.
The announcement that Facebook would share the ads with the Senate and House intelligence committees came after the social network spent two weeks on the defensive. The company faced calls for greater transparency about 470 Russia-linked accounts — in which fictional people posed as American activists — which were taken down after they had promoted inflammatory messages on divisive issues. Facebook had previously angered Congressional staffers by showing only a sample of the ads, some of which attacked Hillary Clinton or praised Donald J. Trump.
Facebook’s admission on Sept. 6 that Russian agents covertly bought ads on the site during last year’s campaign has brought intense scrutiny on the social network and on Twitter, entangling both companies in the investigation by Robert S. Mueller III, the special counsel. Both companies have turned over detailed data to Mr. Mueller.
The disclosure of the ads also raised the possibility of future regulation of political advertising on social media platforms. This week, Congressional Democrats asked the Federal Election Commission to advise on ways to prevent illicit foreign influence on American elections via social media, including possible new laws or regulations.
For Facebook, the move to work with the Congressional committees underscored how far the social network has strayed from being a mere technology company and how it has increasingly had to deal with the unintended consequences of the tools it provides to reach the more than 2 billion people who use the site regularly. The company became more proactive in deflecting criticism this week, with its chief operating officer, Sheryl Sandberg, describing on Wednesday the steps Facebook would take to strengthen its ad system so that it could not be misused to target racists.
On Thursday, in a move clearly intended to pre-empt government intervention, Mr. Zuckerberg outlined the list of actions Facebook planned to take in the coming weeks to make political advertising more transparent. He said each ad will show which Facebook Page — a kind of account required for businesses to create an ad — had paid for the ad, although that would not necessarily identify the people behind the Facebook Page. In addition, Facebook plans to invest more heavily in its security teams, expand its coordination with global election commissions, and work closely with other tech companies to share threat information as it arises.
In his seven-minute talk from Facebook’s headquarters in Menlo Park, Calif., Mr. Zuckerberg suggested there may be additional fake accounts linked to Russia or other foreign countries. “We are looking into foreign actors, including additional Russian groups and other former Soviet states,” he said.
Mr. Zuckerberg, 33, noted that Thursday was his first day back from parental leave after the birth of a daughter. But despite that folksy touch, he had the look of an improbably young leader addressing his people at a moment of crisis.
With his talk of “the democratic process,” “foreign actors,” and “election integrity” — mentioning Germany’s elections this weekend in particular — Mr. Zuckerberg reinforced Facebook’s status as a transnational global behemoth whose power reaches into every corner of contemporary life.
“We are in a new world,” he said. “It is a new challenge for internet communities to deal with nation-states attempting to subvert elections. But if that’s what we must do, we are committed to rising to the occasion.”
Despite Russia’s stealth attack, Mr. Zuckerberg argued that Facebook remained a force for good in democracy, promoting billions of online discussions, linking voters to candidates and helping 2 million Americans register to vote. He said that positive role was “100 or 1,000 times bigger” than the illicit activity.
Twitter, which has kept a low profile since Facebook’s disclosure of the Russian intrusion, has announced that it will brief the Senate Intelligence Committee next Wednesday behind closed doors.
In a statement, Twitter did not address illicit Russian activity on its platform but said it “deeply respects the integrity of the election process, a cornerstone of all democracies” and vowed to “continue to strengthen our platform against bots and other forms of manipulation.”
Senator Mark Warner of Virginia, the top Democrat on the intelligence committee, praised Facebook’s announcement but said he still believed regulation was needed to ensure that voters know more about who is behind ads on social media.
“This is a good first step,” he said. “I’m disappointed it’s taken 10 months of raising this issue before they’ve become much more transparent.” He said he believed there were additional “troll farms” in both Russia and Eastern Europe, “and it’s really important that Facebook work with us to investigate other sources of advertising and fake accounts.”
Mr. Warner said he believed the 3,000 ads, which the committees had not yet received, should be made public with protections for the privacy of any innocent people whose names may be in the material.
Mr. Warner and Senator Amy Klobuchar, Democrat of Minnesota, circulated a letter inviting colleagues to co-sponsor a bill that would require greater transparency for online political ads, according to a copy of the letter seen by The New York Times.
A spokeswoman for Senator Richard Burr, Republican of North Carolina, who is chairman of the intelligence panel, said he had no comment Thursday night.
The Times reported this month that Russian intelligence appeared to have been behind an infestation of Twitter with automated accounts, called bots, that spread messages against Mrs. Clinton last year. The cyber security company FireEye identified what it called “warlists” of hundreds of fake accounts that fired off identical political messages.
The Times also found Facebook accounts that appeared to have been created by ordinary Americans but were actually concocted by Russian agents. Facebook, which had said as recently as July that it had found no evidence of fraudulent Russian ad purchases, reversed itself this month and said it had removed 470 profiles and pages that it said were linked to the Internet Research Agency, a Russian company with ties to the Kremlin.
Facebook found $ 100,000 of ad purchases that were linked to the fake pages — designed to look like the pages of Americans animated by particular issues — that spread inflammatory messages about immigration, guns and other topics; derided Mrs. Clinton and supported Mr. Trump. Facebook shut the accounts down in recent weeks but declined to name or describe them publicly, saying federal law prohibited it from making customer communications public.
Although Facebook had declined to identify the fake Russian pages, The Daily Beast and other news organizations ferreted out a few of them, including one called “Secured Borders” on immigration and another called “Being Patriotic” that promoted pro-Trump rallies in Florida last year.
The illicit Russian exploitation of social media fits squarely into Mr. Mueller’s wide-ranging investigation, and the companies said they have fully cooperated with his requests for detailed data. Though most public attention has been focused on whether the Trump campaign helped with the Russian hacking, leaking and other intrusions, the special counsel’s assignment is “a full and thorough investigation of the Russian government’s efforts to interfere in the 2016 presidential election.”
One question for Mr. Mueller is certain to be whether the Russian Facebook advertising — and any other promotions using Twitter or other services — showed evidence of the kind of sophisticated targeting that might indicate that Americans had provided assistance. Facebook has said some of the ads were targeted to particular geographic areas but has not given details.
For the social media companies, the furor over Russia’s interference raises a possibility that they deeply fear: government regulation, at least for the part of their business that involves political advertising. Political ads on social media have thus far escaped the rules that require, for instance, the familiar “I approve this message” tagline on candidates’ television spots.
Tech executives worry that new rules could hinder the world’s largest digital advertising businesses. Because of the self-service advertising system these tech giants have created, anyone who has an account and a credit card can buy an ad. That has made for a long tail of small-ticket advertisers who add up to millions of dollars in spending.
“Facebook’s number one priority is ad revenue,” said Ian Schafer, chief experience officer of Engine USA, a digital advertising holding company. “The last thing Facebook wants to do is give the government an inch, because then they’ll probably take a mile.”
Last year, Facebook made nearly $ 28 billion in annual revenue, up 57 percent from a year earlier, and the trajectory remains bright. Roughly 97 percent of that revenue came from the company’s ad business.