Facebook is expanding its investigation into potential Russian meddling in Britain's vote on membership in the European Union.
The company told the head of a U.K. parliamentary committee on Wednesday that it would broaden its search for activity aimed at influencing the 2016 Brexit referendum.
"We are committed to making all reasonable efforts to establish whether or not there was coordinated activity similar to that which has been found in the U.S.," Facebook wrote in a letter to Damian Collins, the lawmaker who chairs the committee.
Facebook previously looked for evidence of interference in pages run by the Internet Research Agency, a troll army based in St. Petersburg that has ties to the Kremlin. The group ran a social media operation that targeted U.S. voters, reaching an estimated 150 million Americans through Facebook and Instagram.
Facebook (FB) has said that the IRA bought roughly $100,000 worth of ads targeting Americans. It said late last year that the group had spent less than $1 targeting British voters.
Collins, who is investigating the role of fake news and online misinformation in the U.K., argued at the time that Facebook hadn't looked hard enough.
"It would appear that no work has been done by Facebook to look for other fake accounts and pages that could be linked to Russian backed agencies and which were active during the EU referendum," he tweeted in December.
Related: Facebook told to look harder for Russian Brexit meddling
Facebook said Wednesday that it would resume its search, and asked the British government to provide any intelligence that would help the investigation.
"We have considered your request and can confirm that our investigatory team is now looking to see if we can identify other similar clusters engaged in coordinated activity around the Brexit referendum that was not previously identified," the company said in its letter.
A CNN investigation in November found that a small number of Kremlin-linked Twitter (TWTR) accounts pushed pro-Brexit spin on the morning of the referendum.
In January 2017, the U.S. intelligence community released a report which said that Russia tried to meddle in the U.S. presidential election and had used social media to do it. No similar assessment has been released in the U.K.
Facebook said last week that it would start prioritizing posts from friends and family over content from publishers and brands after a bruising year of stories about fake news, election meddling and social media addiction.
