Questions over alleged censorship have led many to quit the sanitised content aggregator.

Users of the content aggregator Reddit are fleeing to its Swiss rival Voat in what is believed to be a backlash against Reddit’s decision to cut down on "harassing" sub-forums.

The exodus to Voat, which claims to be approaching 100,000 users as of Sunday, was prompted by Reddit’s ban on five "subreddits" which it claimed broke its rules on "harassment of individuals" and coincided with restrictions on users involved with the subreddits.

Writing online Reddit interim CEO Ellen Pao and her team said: "Our goal is to enable as many people as possible to have authentic conversations and share ideas and content on an open platform.

"We want as little involvement as possible in managing these interactions but will be involved when needed to protect privacy and free expression, and to prevent harassment."

Some Redditors have accused the site of engaging in politically motivated censorship, which is out of keeping with the site’s historic commitment to freedom of speech, which in the past has allowed openly racist and sexist communities to flourish.

The change in policy has been attributed to the appointment last November of Pao, who earlier this year lost a discrimination case against her former employer and venture capitalist firm Kleiner Perkins, who dismissed her citing poor performance.

Earlier this month it was also revealed that Pao had banned salary negotiations at Reddit partly because she believed they disadvantaged women.

"We are sorry to see Reddit change like this, in this way, in such an accelerated fashion," said Atko, CTO of Voat, which describes itself as a censorship-free version of Reddit. "We would have never anticipated such events.

"We are not ready for such a huge influx of new users and haven’t prepared for such a large and sudden increase either."

The sanitising of Reddit has coincided with moves from Western governments to gain greater control over the Internet, with the British government clamping down on piracy and certain types of porn during the last year.