- Facebook banned decapitation videos in May due to psychological damage
- In U-turn it says users should be able to watch and condemn these videos
- Hostage UK, which has Ken Bigley's brother as trustee, slams move
- PM calls decision 'irresponsible' and demands Facebook 'addresses problem'
- Child protection groups criticise secret change and call films 'destructive'
- The social network has come under repeated fire for removing pictures which it deems 'indecent' - including one of a woman showing her elbows
A charity supporting British hostages and their families has joined David Cameron in damning Facebook after they lifted a ban on gruesome videos showing Jihadists beheading people.
Hostage UK, which is supported by the family of murdered engineer Ken Bigley, today accused the social network of 'playing into the hands of hostage-takers' by allowing footage of decapitations.
It came as the Prime Minister condemned Facebook as 'irresponsible' to secretly change its policy and said it must justify its actions to parents and users of the site.
The U.S. firm had banned footage of executions on its site in May citing concerns that it would cause long-term psychological damage, but it emerged today it had quietly performed a U-Turn.
Terrible: The filmed executions of people like Ken Bigley, left, will be allowed to be shown on Facebook after they quietly lifted a ban, which David Cameron, pictured today, called 'irresponsible'
Facebook, which is open to anyone over the age of 13, now claims its users should be able to watch as long as they condemn these videos, not celebrate them.
Critical: Hostage UK, a charity supported by Ken Bigley's brother Phil, pictured, has accused Facebook of 'playing into the hands of hostage-takers'
Its rules mean that users are not allowed to put up pictures of breasts, for example, but can post a video showing a hostage being murdered.
Former head of the Hostage And Crisis Negotiation Unit at Scotland Yard, Sue Williams, who is also a trustee of Hostage UK told MailOnline: 'Facebook is playing into the hands of the hostage-takers, who use these videos to instil fear. By stopping the ban they are, in effect, now doing their job for them.
'I do not think that Facebook has thought through the full consequences of this.
'It will cause great pain to the families of those who have lost loved-ones who were hostages. Facebook must also think about of those who are being held hostage at present'.
The brother of Ken Bigley, Phil Bigley, is a trustee of Hostage UK and supports their work.
His 62-year-old sibling, from Walton, Liverpool, was taken hostage by Muslim extremists while working in Baghdad on September 16, 2004.
He was filmed being beheaded more than three weeks late on camera.
The controversial decision by Facebook to allow videos like this to be allowed on the website has led to David Cameron condemning the move.
'It's irresponsible of Facebook to post beheading videos, especially without a warning,' the Prime Minister wrote on Twitter.
'They must explain their actions to worried parents.'
His official spokesman added: 'He does think the company should address this problem'.
Criticism: David Cameron used rival site Twitter to hit out Facebook's new policy
Gruesome videos of people being beheaded are to be allowed on Facebook once again. The social network claims that its users should be able to watch and condemn these videos, but not celebrate them
Suicide prevention charities also condemned the decision saying the material is 'psychologically destructive'.
'It only takes seconds of exposure to such graphic material to leave a permanent trace - particularly in a young person's mind,' Dr Arthur Cassidy, who runs the Yellow Ribbon Program in Northern Ireland, said today.
'The more graphic and colourful the material is, the more psychologically destructive it becomes.'
The change in policy was brought in quietly and only discovered by a user who said Facebook was refusing to remove a page showing a clip of a masked man killing a woman.
'This is absolutely horrible, distasteful and needs to be removed... there are too many young minds that can see this. I'm 23 and I'm very disturbed after seeing a couple of seconds of it,' wrote one user.
Despite now allowing decapitation footage, the social network's terms and conditions say it will continue to remove banned material including an exposed woman's breasts.
'Photos that show a fully exposed breast where the child is not actively engaged in nursing do violate the Facebook Terms,' the site said.
'These policies are based on the same standards which apply to television and print media.'
The site, which is open to anyone over the age of 13, had banned footage of decapitation on its site in May citing concerns that it would cause long-term psychological damage
But the social network has come under repeated fire from mothers whose pictures showing children breast-feeding are deleted and their accounts closed.
Last year, the group banned a picture of a woman reclining in her bath tub with the only nudity visible being her shoulder and her elbow, although the pose appeared to be inappropriate.
The snap was uploaded by web magazine Theories of the Deep Understanding of Things to test how the social network's terms of service deal with pictures that are misleading.
It posed the question of whether the photo-sharing website content policies are based on indecency or the mere appearance of indecency.
'Since some people object to graphic video of this nature, we are working to give people additional control over the content they see,' said a spokesperson for Facebook.
'This may include warning them in advance that the image they are about to see contains graphic content.'
FACEBOOK RULES: BEHEADINGS ARE ALLOWED BUT BREASTS ARE BANNED
Facebook may now allow videos of people being beheaded, but there are a number of subjects and clips it will not allow to be published on in its site.
Facebook has a strict policy against the sharing of pornographic content and any explicitly sexual content where a child is involved.
Elsewhere, the site imposes 'limitations on the display of nudity' but doesn't ban it outright - it depends on the context and circumstance.
Female nipples, as a rule, will be removed but male nipples are allowed. A photo was famously removed last year when an elbow was mistaken for a female nipple, before being reinstated.
Breastfeeding images were removed in 2012, but Facebook's Community Guidelines now states the site 'respects people's right to share content of personal importance' and makes explicit reference to breastfeeding.
The pictures are allowed if the child is seen 'actively nursing' but may be removed if it shows the nipple. Children playing in the bath are accepted as long as they are not graphic and explicit, while sculpture and art work that depicts the naked body is allowed, but real-life images and similar poses are not.
Another photo famously taken down showed Kylie Minogue holding a teddy bear, pictured right, with her microphone positioned in such a way, between the bear's legs, that made it look phallic. Facebook removed it for violating the use of 'photos that contain nudity, drug use or violence.'
Any video that condones violence, threatens or is abusive and bullying towards another person or promotes criminal activity is prohibited. Any promotion or encouragement of self-mutilation, eating disorders of drug abuse is similarly banned.
Facebook does not permit hate speech, especially towards individuals, groups, sex, race, ethnicity, disability or sexual orientation yet will distinguish between 'serious and humorous speech' and will allow videos and posts that 'challenge ideas, institutions and certain practices.'
Sharing graphic content for 'sadistic pleasure' is prohibited, yet if the content is shared in the process of reporting current events it is be allowed as long as it balances 'the needs of a diverse community.'
Facebook monitors photos, but also relies on its users to report content they feel should be removed. If a photo is under investigation it may be temporarily removed while Facebook looks into the complaint but will be reinstated if it is found not to have breached the code.