San Francisco, Dec 23 (IANS): Coming under intense scrutiny for failing to prevent alleged Russian propaganda from spreading on its platform during the 2016 US presidential election, Facebook has introduced a tool that lets some users check if they interacted with such posts in the run up to the election.

The tool available through its Help Center specifically allows users to see if they followed or "Liked" any pages and accounts set up by Kremlin-backed trolls on either Facebook or Instagram, Recode.net reported on Friday.

According to a Facebook estimate, roughly 140 million users might have seen Russian propaganda in their News Feeds or on Instagram over the course of the 2016 election.

But only a fraction of those 140 million affected users can actually make use of Facebook's new tool.

The portal only helps those who directly followed one of the accounts or pages set up by Russian sources on Instagram and Facebook.

It does not aid users who may have simply seen Russian-sponsored content because their friends "Liked" it and it subsequently appeared in their own News Feeds, the Recode report said.

Facebook's new service also does not allow users to check if they saw some of the roughly 3,000 election-timed ads purchased by trolls linked to Russia.