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Facebook says it's creating a tool that will show users if they "liked" or followed fake Russian accounts spreading propaganda on its site or on Instagram during the 2016 presidential election.

The new portal will allow users to see which Russian accounts they followed between January 2015 and August 2017, Facebook announced Wednesday. The company said it will be available for use through its “Help Center” by the end of the year.

"It is important that people understand how foreign actors tried to sow division and mistrust using Facebook before and after the 2016 US election," Facebook said in a blog post.

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"That’s why as we have discovered information, we have continually come forward to share it publicly and have provided it to congressional investigators. And it’s also why we’re building the tool we are announcing today.”

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Some of the Facebook and Instagram ads linked to a Russian effort, released by members of the U.S. House Intelligence committee, on Nov. 1, 2017. Jon Elswick / AP file

But the tool will only show if users "followed" the pages, not if they only saw or “liked” posts that were originally posted on them, Facebook said.

The portal will specifically show accounts associated with the Russian Internet Research Agency that attempted to propagate polarizing views on divisive social and political issues with posts and advertisements based on race, religion, immigration, gun rights, as well as LGBT rights.

“This is an important step,” Facebook COO Sheryl Sandberg said in a post. “We have a responsibility to share the information we’ve found about foreign interference on our platforms – and we’re committed to help prevent it from happening again.”

In September, Facebook said the operation likely spent $100,000 on thousands of those ads for a two-year period that ended in May.

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About one-third of the U.S. population — an estimated 126 million Americans — were exposed to Russian-linked content on Facebook during the 2016 campaign, according to company officials.

Facebook, Google and Twitter were slammed by lawmakers earlier this month and acknowledged that they failed to prevent Russia from spreading propaganda on their platforms in a coordinated effort to influence the 2016 presidential election.

At those hearings, Sen. Dianne Feinstein, D-Calif., told tech company officials "You bear this responsibility. You've created these platforms. And now they are being misused. And you have to be the ones to do something about it. Or we will."

Rep. Adam Schiff, D-California, said the new portal was a "very positive step" in a statement. But he said he's still looking for more information about Russia’s efforts, including a joint report by the companies “on how Russia used these platforms to sow discord and influence the election.”