Twitter's Carlos Monje, the director of public policy and philanthropy, right, and Colin Crowell, head of global public policy, prepare to enter a closed-door meeting of the House Intelligence Committee on Capitol Hill on Sept. 28. (Alex Brandon/AP)

Twitter said Thursday that it had shut down 201 accounts that were tied to the same Russian operatives who posted thousands of political ads on Facebook, but the effort frustrated lawmakers who said the problem is far broader than the company appeared to know.

The company said it also found three accounts from the news site RT — which Twitter linked to the Kremlin — that spent $274,100 in ads on its platform in 2016.

Despite the disclosures, Sen. Mark R. Warner (D-Va.) questioned whether the company is doing enough to stop Russian operatives from using its platform to spread disinformation and division in U.S. society.

Warner said Twitter's presentation to a closed-door meeting of Senate Intelligence Committee staffers Thursday morning was "deeply disappointing" and "inadequate on almost every level." Twitter also made a presentation to House Intelligence Committee staffers in the afternoon.

The company "showed an enormous lack of understanding . . . about how serious this issue is, the threat it poses to democratic institutions," a visibly frustrated Warner said.

The meetings between the company and congressional investigators were part of a widening government probe into how Russian operatives used Facebook, Twitter, Google and other technology platforms to widen fissures in the United States and spread disinformation during the 2016 campaign. Those companies have come under increasing pressure from Capitol Hill to investigate Russian meddling and are facing the possibility of new regulations that could affect their massive advertising businesses.

[Russian operatives used Facebook ads to exploit America’s racial and religious divisions]

The Washington Post reported this week that some of the 3,000 Facebook ads bought by Russian operatives promoted African American rights groups, including Black Lives Matter. Those ads were targeted at users in specific locations such as Ferguson, Mo., and Baltimore, two cities that have faced violent protests over police shootings of black men. Ads aimed at voters in other regions, meanwhile, suggested that the same groups posed a rising political threat.

Other ads featured Muslims supporting Democrat Hillary Clinton for president and were targeted at Facebook users who might fear Muslims.

Facebook, Google and Twitter are being summoned to a public hearing before the Senate Intelligence Committee on Nov. 1.

The Twitter accounts, which were taken down over the past month, were associated with 470 accounts and pages that Facebook this month said came from the Internet Research Agency, a Russia-connected troll farm. Twitter said the groups on Facebook had 22 corresponding Twitter accounts. Twitter then found an additional 179 accounts linked to those 22.

But lawmakers and analysts criticized Twitter for appearing to have accepted and looked into only the data that it had received from Facebook, rather than conducting a broader internal investigation.

Rep. Adam B. Schiff (Calif.), the ranking Democrat on the House Intelligence Committee, said Twitter needs to launch "a far more robust investigation" into how Russian actors are using its site, adding that "there are serious questions about whether Twitter has the capability to do the forensics necessary to determine how much the Russians used their platform."

In a blog post, Twitter did not reveal who was targeted by the ads or how many times they were shared. Twitter declined to comment on whether it had conducted a broader search of its users for Russian interference. The company wrote that it is continuing its investigation and anticipated having more information to share later.

[Did Facebook ads traced to a Russian company violate U.S. election law?]

Twitter said it was cooperating with the congressional investigation. "Twitter deeply respects the integrity of the election process, which is a cornerstone for all democracies. We will continue to strengthen Twitter against attempted manipulation, including malicious automated accounts and spam, as well as other activities that violate our Terms of Service," its blog post said.

Alexander B. Howard, deputy director of the Sunlight Foundation, said there is plenty of evidence that Russian intelligence operatives have been on Twitter for years and have used the platform to amplify messages.

"We need to think very carefully about what role we want these companies to have in our debate — and since these platforms largely regulate themselves, what kind of accountability we want them to have," Howard said.

Silicon Valley has long enjoyed a hands-off approach from regulators and has become a major lobbying force in Washington to keep things that way. But that attitude appears to be shifting quickly.

Last week, Warner and Sen. Amy Klobuchar (D-Minn.) urged colleagues to support a bill that would create new transparency requirements for platforms that run political ads online, akin to those in place for television stations, according to a letter obtained by The Post. Lawmakers from across the political spectrum — including Sen. Cory Booker (D-N.J.) and Sen. Ted Cruz (R-Tex.) — have called over the past few months for more scrutiny of the market power of technology companies.

Silicon Valley companies that are targets of the Russia investigation have privately complained that law enforcement and intelligence officials have not shared information with them that could help them catch bad actors.

Facebook has faced the greatest scrutiny. The company has said it will provide the 3,000 political ads, in addition to payment information and data about who those ads targeted, to Congress in coming days.

Facebook chief executive Mark Zuckerberg, in a post on the social media platform Wednesday, apologized for saying it was "pretty crazy" that fake news could have influenced the U.S. election.

"Calling that crazy was dismissive and I regret it. This is too important an issue to be dismissive," he wrote. He then emphasized that the role Facebook played in spurring authentic debate and sustaining democratic ideals was much greater than any exploitation that took place.

[Mark Zuckerberg denies that fake news on Facebook influence the elections]

"The data we have has always shown that our broader impact — from giving people a voice to enabling candidates to communicate directly to helping millions of people vote — played a far bigger role in this election," he said.

Google, the largest online advertising company in the world, also has been asked to provide information to congressional investigators and to testify before Congress, but it has not said whether it will do so. The company has said that it will cooperate with any investigation and that it has "seen no evidence" of a ­Russian-promoted ad campaign. Google did not respond to repeated requests for comment.

In many ways, Twitter has been the most vulnerable to exploitation among social media companies. The company officially says that 5 percent of accounts on Twitter are bots, but outside researchers say the number could be much higher.

It is easy to create fake accounts on Twitter, making it hard for the company to discern the extent of Russian meddling, analysts said.

"They have no idea who is on their platform. If it wasn't for Facebook's data, they would have no idea these were even Russian accounts," said Clint Watts, senior fellow at the Foreign Policy Research Institute. "Anyone can create an account anonymously on Twitter and hide its origin."

Entous and Demirjian reported from Washington.