Facebook's investigation into whether Russia tried to influence Britain's vote to leave the European Union yielded just three suspicious ads viewed no more than 200 times over four days, the social media firm said Wednesday.
The three ads created by the Moscow-linked Internet Research Agency, cost 97 cents.
They did not feature any direct information about the EU referendum, known as Brexit. Rather, they mentioned immigration. The three ads also targeted U.S. audiences.
Britain's Electoral Commission had requested that Facebook look into any dubious activity in last year's Brexit vote after an earlier probe by the firm into alleged Russian meddling in the U.S. election uncovered more than 3,000 ads targeting U.S. voters.
The ads targeting U.S. voters were run from 470 fake or inauthentic accounts and pages linked to the Internet Research Agency, which spent around $100,000 on them.
Moscow has consistently denied trying to meddle in the Brexit vote. However, in a speech last month Prime Minister Theresa May accused Russia of interfering in elections, spreading fake news and cyber-espionage.
The Electoral Commission has also sought information from Google and Twitter. A series of British academic studies have concluded that thousands of Russian-based Twitter accounts posted Brexit-related tweets during the referendum campaign.
Google and Twitter have not publicly released their findings.
The Electoral Commission said in a statement that it welcome the technology firms' cooperation, but added: "There is further work to be done with these companies in response to our request for details of campaign activity on their platforms funded from outside the U.K. Following those discussions we will say more about our conclusions."
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