Russian propagandists targeted the popular news-sharing website Reddit to influence American political debate, a US website has claimed.
It had been widely presumed that Reddit, a hub for campaigning, activism and often extreme views, would be a logical target for any manipulation.
It has yet to publish its own investigation into Russian activity.
Now it has obtained files showing a Russian troll farm was active on Reddit, reports BBC citing The Daily Beast.
The Daily Beast says it has obtained leaked documents from within Russia's Internet Research Agency (IRA), the country's most prominent troll-factory.
The US government has already charged 13 Russians, linked to the agency, with attempting to manipulate American voters using social media.
The Russian organisation is alleged to have had a budget of more than a million dollars, which the US claims was used to buy advertising on sites such as Twitter and Facebook.
So far, Reddit has not been included in the US Senate's investigation into Russian meddling in the 2016 presidential election.
But some reports have suggested that could soon change.
Influence
The documents discovered by the Daily Beast are said to detail the Internet Research Agency's efforts on Reddit.
The site says the agency employed "online agitators" to help posts from its own propaganda websites rise to the top of Reddit.
It says the organisation used proxy servers to mask the location of its work.
Also targeted were the Yahoo-owned blogging platform Tumblr, and the viral joke site 9gag.
As has been a pattern with Russian efforts discovered to date, there is no outright support of any particular candidate or viewpoint.
Instead it seems Russia's aim was to provoke and divide Americans on the internet and, as a result, in the physical world too.
'Not provided evidence'
The Daily Beast said it had given Reddit the opportunity to comment on the story, but that repeated requests were ignored.
Reddit replied on Friday, telling the BBC: "Reddit was not provided evidence of accounts or other data that would enable us to identify misuse or manipulation of the platform by users."
Reddit has gained a reputation as being something of a haven for some of the more extreme views that have been pushed off other platforms like YouTube and Twitter.
The site consists of many user-generated sections, known as subreddits, that focus on a particular topic or place, such as r/football or r/SanFrancisco.
In a move he later apologised for, Reddit co-founder and chief executive Steve Huffman admitted personally editing comments posted on r/The_Donald.
'Disturbing'
Aside from information involving Reddit, the Daily Beast said the leaked documents included "at least 21" accounts on Tumblr, the blogging site acquired by Yahoo in 2013.
Facebook, Twitter and YouTube-owner Google have all appeared in front of US politicians on several occasions to explain their investigations and subsequent efforts to prevent similar activity from Russia - or other countries - in the future.
