People worried that their Facebook friends are suicidal will be able to alert the Samaritans via the social networking site.

It comes after the friends and family of a woman who announced on Facebook that she would be taking her own life demanded to know why no one helped her.

Simone Back, 42, was pronounced dead in hospital on Boxing Day less than 24 hours after threatening on the website to take an overdose.

Ms Back, from Brighton, East Sussex, posted on Facebook on Christmas Day: “Took all my pills be dead soon so bye bye every one.”

There have also been reports of other people writing messages before attempting suicide.

The Samaritans and Facebook announced they are creating a “pioneering new scheme” to allow people to get help for a friend they believe is struggling to cope.

Friends are urged via Facebook’s help centre (www.facebook.com/help) to call the Samaritans if they see suicidal content, and if the content suggests somebody is imminently about to take their life people are advised to call the police.

They are also directed to a Facebook form where they can copy in the URL address of the page where they have seen a worrying status update or wall post. They can do this anonymously.

Facebook will then pass on the name and e-mail address of the vulnerable person to the Samaritans, who will get in touch within 12 hours.