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A Reddit user who posted leaked UK government documents was part of a larger coordinated effort that appears to have originated in Russia, Reddit said in a security announcement Friday. A network of connected accounts re-posted the documents in several forums on the discussion website and manipulated Reddit's voting system for highlighting popular content, all in an effort to bring more attention to the leaks.

"We were recently made aware of a post on Reddit that included leaked documents from the UK," the company said in its blog post. "We investigated this account and the accounts connected to it, and today we believe this was part of a campaign that has been reported as originating from Russia."

The leaked documents originated from the UK Department for International Trade, and recorded negotiations for a future trade deal between the US and the UK. They were posted on Reddit in October but didn't stir controversy until Member of Parliament Jeremy Corbyn discussed them publicly in November.

While Reddit says it has been concerned about users abusing the site since its launch in 2005, it has launched a larger effort to identify what it calls "state actors interested in interfering with elections and inflaming social divisions" over the past two years. Research by a computer scientist in 2017 found evidence of a targeted effort to manipulate discourse aimed at conservative subreddits around the time of the 2016 presidential election. In 2018, Reddit acknowledged that a web of accounts had promoted propaganda originating in Russia in two years earlier.

On Friday, Reddit said it had banned a discussion forum, known on Reddit as a subreddit, dedicated to the UK leaks, in addition to banning the accounts it identified as belonging to the group. Reddit said it believes the accounts were run by the same group that tried similar tactics on Facebook in May. Digital forensic investigators at the Atlantic Council call the group Secondary Infektion and believe it originates in Russia.

"All of these accounts have the same shared pattern as the original Secondary Infektion group detected, causing us to believe that this was indeed tied to the original group," Reddit said.