Facebook said on Wednesday it had found that an influence operation probably based in Russia spent $100,000 on ads promoting divisive social and political messages in a two-year-period through May.

The social media network said that many of the ads promoted 470 “inauthentic” accounts and pages Facebook has now suspended. The ads spread polarizing views on topics such as immigration, race and gay rights, instead of backing a particular political candidate, it said.

Facebook announced the findings in a blogpost by its chief security officer, Alex Stamos, and said that it was cooperating with federal inquiries into influence operations during the 2016 presidential election.

The company said it found no link to any presidential campaign. Three-quarters of the ads were national in scope, and the rest did not appear to reflect targeting of political swing states as voting neared.

Facebook did not print the names of any of the suspended pages, but some of them included such words as “refugee” and “patriot”.

The findings buttress US intelligence agency conclusions that Russia was actively involved in shaping the election.

Facebook previously published a white paper detailing well-funded and subtle techniques used by countries and organizations to spread misleading information for geopolitical goals. These efforts go well beyond “fake news”, the company said, and include content seeding, targeted data collection and fake accounts used to amplify one particular view, sow distrust in political institutions and spread confusion.

The company said in April: “We have had to expand our security focus from traditional abusive behavior, such as account hacking, malware, spam and financial scams, to include more subtle and insidious forms of misuse, including attempts to manipulate civic discourse and deceive people.”

Facebook did not attribute the manipulation to any nation state, although it said that the company’s investigation “does not contradict” the findings of a January report by the US director of national intelligence that outlined Russian involvement in the election.

Even so, as recently as June, it told journalists that it had not found any evidence to date of Russian operatives buying election-related ads on its platform.

A Facebook employee said on Wednesday there were unspecified connections between the divisive ads and a well-known Russian “troll factory” in St Petersburg that publishes comments on social media.

Beyond the issue ads, Facebook said it uncovered $50,000 more in overtly political advertising that might have links to Russia. Some of those ads were bought using the Russian language, even though they were displayed to users in English.

Even if no laws were violated, the pages ran afoul of Facebook requirements for authenticity, setting up the suspensions.

“In the past Facebook has taken the stance that it’s a tech company and not a media company, but they have clearly moved into the media company category,” said advertising veteran Mike Kelly, CEO of Kelly Newman Ventures and former president of AOL Media. “They have to up their game a bit.”

Kelly suggests that the company should use its technology prowess to come up with “new ways to filter and assess accounts and advertisers”.

Facebook, which now has 2 billion monthly users, suspends more than 1 million accounts per day in its quest to keep spam, fraud and hate speech of its platform.

More than $1bn was spent on digital political ads during the 2016 presidential campaign, 10,000 times the amount identified by Facebook’s security team.

Facebook has rejected the notion that fake news on Facebook influenced the outcome of the US election, with Mark Zuckerberg describing it as a “pretty crazy idea”.

“Voters make decisions based on their lived experience,” he said in November.

But Facebook’s ad sales team tells a different story. It highlights how an “audience-specific” political campaign on Facebook was able to “significantly shift voter intent and increase favorability” for US senate candidate Pat Toomey, contributing to his re-election.

In other words: it is entirely possible to swing an election using Facebook advertising, but it doesn’t seem like this Russian “influence operation” was effective.

“Maybe nothing happened this time, but it’s a good warning to them that their [Facebook’s] role in the media landscape has changed, especially given their scale, and with that comes a lot of new responsibility,” said Kelly.