Facebook and other social networking sites have been criticised for hosting a number of anti-Semitic, homophobic and racist web pages.

According to a report from the Simon Wiesenthal Centre, a Jewish human rights group named after the renowned Nazi-hunter, there has been a 25 per cent rise in the number of hate groups hosted on sites such as YouTube.

Researchers found more than 10,000 websites, social networking groups, portals, blogs, chat rooms, videos and hate games that promoted racial violence, anti-Semitism, homophobia, hate music and terrorism.

They found groups such as Croatian Srmt Pederima (Death to gays) and a Serbian group expressing hate towards gays and prostitutes.

It was also found that white supremacist group Stormfront was using its Facebook page to connect thousands of visitors to its main website.

Recently, Facebook was forced to remove two Holocaust-denying groups after complaints from other users.

The two groups, ‘Holocaust is a Holohoax’ and ‘Based on the facts … there was no Holocaust’ were taken down at the weekend.

Along with gays and Jews, Catholics, Muslims, Hindus, women and immigrants were some of the most targeted groups.

A statement from the Simon Wiesenthal Centre said: “Every aspect of the internet is being used by extremists of every ilk to repackage old hatred, demean the ‘Enemy’, to raise funds and, since 9/11, recruit and train Jihadist terrorists,”

“This user-generated material increases the viral spread of extremism online and aids in increasing the social acceptability of hate in mainstream discourse.

“By creating an environment where users are equal participants in the web, all editorial functions are removed and expressions of hate can easily flow unchallenged.”

A Facebook spokesman told The Times that “the mere statement of denying the Holocaust is not a violation of our terms”.

According to the company’s statement of rights and responsibilities, users may not “post content that is hateful, threatening, pornographic, or that contains nudity or graphic or gratuitous violence”.

Facebook said in a statement: “Many of the groups or pages that were shown to us by the Simon Wiesenthal Centre earlier this year as part of their study had already been removed under Facebook’s rules.

“We are committed to continuing this practice, and to working with those who fight hate like the Simon Wiesenthal Centre.”

In December, Facebook was asked by users to remove Serbian homophobic groups.

The groups, “Queeria, Pederi Marš iz Srbije”and “СТОП ПЕДЕРИМА – КВИРИЈИ!” were actively promoting homophobic abuse.

Users of the groups posted death threats to gay and lesbian Serbians, and called for attacks on gay people and their property.

The members of the group also sent hate mail to LGBT activist leaders, and publicised their names, addresses and telephone numbers, raising serious concerns about security and proper use.