Facebook says that it displayed Russia’s divisive election ads to 10 million people, most of whom saw the ads after the election was over. It’s not clear how many impressions that equates to (it’s possible one person saw multiple ads), but Facebook says that 44 percent of the ads were displayed before the 2016 election, and 56 percent came after. Facebook says it’s identified more than 3,000 ads in total, stemming from a Kremlin-linked group known as the Internet Research Agency.

The details were released following Facebook’s disclosures to Congress earlier today. The company shared the 3,000-some ads with legislators and committed to hiring 1,000 more moderators to review ad placements in the future.

“Most of the ads appear to focus on divisive social and political messages.”

Facebook says that a quarter of the ads it identified were never shown to anyone, likely because they were targeted to too specific of a group.

“Most of the ads appear to focus on divisive social and political messages across the ideological spectrum, touching on topics from LGBT matters to race issues to immigration to gun rights,” writes Elliot Schrage, Facebook’s policy VP. “A number of them appear to encourage people to follow Pages on these issues.”

Today’s disclosure reveals the extent to which Russia’s propaganda was allowed to spread over the platform. The Internet Research Agency is believed to have paid Facebook $100,000 to promote the ads, simply by going through Facebook’s normal ad-placement tools, which are open to anyone.

Facebook says, in fact, that many of the Internet Research Agency’s ads wouldn’t have violated its terms of service if the group hadn’t misled viewers about who was behind them. “Most of [the ads], if they had been run by authentic individuals, anywhere, they could have remained on the platform,” Schrage writes. He also adds that, “If Americans conducted a coordinated, inauthentic operation — as the Russian organization did in this case — we would take their ads down, too.”

In response, Facebook says it’s putting in new safeguards to prevent abuse of its ad tools. In addition to hiring reviewers, it’s also going to require that advertisers “confirm the business or organization they represent,” potentially helping to weed out fake groups.

Even before Facebook disclosed these figures, it was becoming increasingly clear that Russia’s ads had made an impact. The Daily Beast found evidence of Russian actors successfully organizing pro-Trump rallies on Facebook, while other Russian-created political pages gained followers, shared memes, and posted hateful rhetoric.