Facebook found "no evidence of a significant attempt by outside forces" such as Russia to use the social network to influence Britain's vote in 2016 to leave the European Union, a company executive said Monday.
Nick Clegg, the former UK deputy prime minister who now leads Facebook's communications team, told the BBC in an interview that the world's largest social network ran two analyses in the run-up to Brexit and couldn't find proof of interference by other countries.
During the interview, Clegg was asked if he questioned whether Facebook was used to change the results of the 2016 referendum.
"There's absolutely no evidence that it happened in the Brexit referendum," he responded.
Some UK lawmakers questioned whether Clegg's remarks were true.
"Horse manure," wrote Labour Party lawmaker David Lammy in a tweet on Monday. "What about the disinformation spread by Russian state media, RT and Sputnik, on Facebook?"
Damian Collins, chairman of the Digital, Culture, Media and Sport select committee, also criticized Clegg's remarks in a tweet.
The Russian government has denied meddling in the US and UK elections.
Clegg also dismissed the idea that UK political consultancy firm Cambridge Analytica, which came under fire for harvesting the data of up to 87 million users without their permission, influenced the Brexit referendum. A UK watchdog, he said, found that the data of UK users wasn't involved in the breach.
"Facebook has a heavy responsibility to protect the integrity of elections from outside interference," he said. "I also think we have a duty to explain facts from some of the allegations that have been made."
CNET asked Facebook for the analyses Clegg referenced, but the company didn't immediately respond to a request for comment.
Other social networks such as Twitter have found a small number of Russian accounts that tried to influence the Brexit vote.