SAN FRANCISCO — Those divisive political ads from Russians trying to sway the U.S. presidential election in favor of Donald Trump? Yep, they ran on Instagram, too.

Facebook says 5% of the 3,000 ads that appeared on Facebook also appeared Instagram. About $6,700 was spent on the Instagram ads, the Silicon Valley company said Friday in an update to a previous blog post. All of the ads generated about $100,000 for Facebook.

Facebook says it unknowingly sold the politically inflammatory ads to a Russian troll farm linked to the Kremlin called the International Research Agency, which unleashes fake social media accounts to stir controversy and conflict. 

It's unclear how many people saw the Instagram ads. Facebook said this week that as many as 10 million people saw the ads on Facebook. 

Facebook has come under harsh scrutiny over its disclosure that Russians bought thousands of ads to spread divisive messages during and since the presidential election. It has turned those ads over to congressional investigators but has refused to make them public. The ads were designed to heighten political discontent by focusing on hot-button issues such as gun control, Black Lives Matter and immigration.

More: Facebook political ads are coming out of the shadows — why you should care

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More: USA TODAY Poll: Facebook faulted for not doing more on Russian ads in 2016 race

More: Russian meddling in 2018 elections may prove difficult for Congress to stop

Facebook, Google and Twitter are under increasing pressure to investigate Russian meddling on their services. 

Twitter told lawmakers it found some 200 accounts linked to the same Russian groups. 

Facebook has been called to testify before the House and Senate Intelligence Committees on Nov. 1. The two intelligence panels, along with the Senate Judiciary Committee and special counsel Robert Mueller, are investigating Russia's interference in last year's election. They also are looking into possible collusion between the Trump campaign and Russian officials.

The U.S. intelligence community, in a report released in January, concluded that Russia was trying to sway the election in favor of Trump and against Democrat Hillary Clinton.