Free speech row after journalist sought to reveal identity of man running forums featuring extreme adult content

Blog network Gawker has found itself engaged in a vicious exchange with users of content sharing and recommendations website Reddit's sleazier sub-forums after a journalist began investigating extreme adult content on the site.

One Reddit politics forum has banned links to Gawker after what the moderator described as "an attack on the site and its users", in an escalating row over free speech versus privacy and the publication of offensive material on the web.

The focus on Reddit's less salubrious content will be an embarrassment for owner Condé Nast, publisher of Vanity Fair and Vogue, which bought the site in 2006.

Gawker journalist Adrian Chen began investigating one prolific Reddit user, Violentacrez, who has set up hundreds of sub-forums where users post links and images including bestiality, rape fantasy, under-age porn and upskirt photos.

Violentacrez most recently joined "Creepshots", a forum of stalking-style pictures of women taken without their consent. The forum was taken down last night and has now been banned.

The same user posted last week's email exchange with Chen on a Reddit forum seeking advice, but was apparently so concerned that his identity would be revealed that he later deleted his account.

In response, the Reddit forum's volunteer moderator PoliticsMod on Thursday published a statement about Gawker's "intolerable" behaviour, characterising Chen's investigation as an attack on the site's users.

"We volunteer our time on Reddit to make it a better place for the users, and should not be harassed and threatened for that. We should all be afraid of the threat of having our personal information investigated and spread around the internet if someone disagrees with you. Reddit prides itself on having a subreddit for everything, and no matter how much anyone may disapprove of what another user subscribes to, that is never a reason to threaten them.

"As a result, the moderators of /r/politics have chosen to disallow links from the Gawker network until action is taken to correct this serious lack of ethics and integrity."

The post triggered thousands of comments on the site and a slew of lengthy defences by PoliticsMod, who claimed that Gawker has previously attempted to reveal the identities of Reddit posters, undermining their safety.

The Guardian has asked Reddit for comment and to clarify its user guidelines for content posting. It has deleted previous sub-forums including r/jailbait.

The Creepshots controversy has triggered a backlash among Reddit users defending the right to post freely, and those who object to offensive, invasive and threatening content objectifying women.

Jezebel has reported that Creepshots included content posted by a teacher of "a hot senior girl in one of my classes".

One new Tumblr project, Predditors, is now identifying and naming Reddit contributors behind objectionable content, according to BetaBeat.

Traffic tool Alexa lists Reddit as the 65th most popular site in the US. Some of its mainstream sub-forums, such as r/funny, have reached peaks of 9m impressions in one day. Alexa characterises Reddit's user base as predominantly male, between 18 and24, with no children and still in education.

In August, President Obama triggered a surge of traffic to the site when he joined a late night Q&A on internet freedom.

"We will fight hard to make sure that the internet remains the open forum for everybody," Obama wrote. "Sure thing," replied a user. "Do you like cats?"

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