Social media giant Facebook is expected to provide Congress on Monday with more than 3,000 ads that ran around the time of the 2016 presidential election and are linked to a Russian ad agency.

Company officials will meet with the House and Senate intelligence committees and the Senate Judiciary Committee to hand over the ads, a Facebook official said. The official requested anonymity because the meetings are private.

Facebook said last month that that it had found thousands of ads linked to Facebook accounts that likely operated out of Russia and pushed divisive social and political issues during the US presidential election. The company said it found 450 accounts and about $100,000 was spent on the ads.

Twitter has said it found postings linked to those same accounts, and the House and Senate intelligence panels have asked both companies, along with Google, to testify publicly in the coming weeks.

None of the companies have said whether they will accept the invitations.

The three committees are investigating Russian meddling in the election and whether there are any links to President Donald Trump’s campaign. They have recently focused on the spread of false news stories and propaganda on social media, putting pressure on the companies to turn over more information and release any Russia-linked ads.

It is unclear whether the ads will eventually be released publicly. Several lawmakers — including Virginia Senator Mark Warner, the top Democrat on the Senate intelligence panel — have said they believe the American public should see them.

Facebook CEO Mark Zuckerberg announced September 21 that the company would provide the ads to Congress and also make changes to ensure the political ads on its platform are more transparent. The company is also working with Special Counsel Bob Mueller’s investigation into the Russian meddling at the Justice Department.

“As a general rule, we are limited in what we can discuss publicly about law enforcement investigations, so we may not always be able to share our findings publicly,” Zuckerberg said. “But we support Congress in deciding how to best use this information to inform the public, and we expect the government to publish its findings when their investigation is complete.”

Facebook said the ads addressed social and political issues and ran in the United States between 2015 and 2017. The company said the ads appear to have come from accounts associated with a Russian entity called the Internet Research Agency.

Twitter said last week that it had suspended 22 accounts corresponding to the 450 Facebook accounts that were likely operated out of Russia.

Warner criticised Twitter for not sharing more information with Congress, saying the company’s findings were merely “derivative” of Facebook’s work. The company’s presentations to staff last week “showed an enormous lack of understanding from the Twitter team of how serious this issue is, the threat it poses to democratic institutions.”