Some of the UK's most wanted child sex offenders have been identified online.
The men have failed to comply with the sex offenders' register
It is believed to be the first time that details of convicted paedophiles have been published nationwide by Britain's law enforcement agencies.
The Child Exploitation and Online Protection (CEOP) centre has set up the new website in an effort to track missing child sex offenders.
Meanwhile, single mothers could be able to check up on new partners to see if they are sex offenders under new plans.
The Home Office is considering proposals that would enable single mothers to ask the police to make the checks, which would have to be supported by reasonable grounds for suspicion.
It is known that predatory paedophiles often befriend single mothers as a way of gaining access to their children.
Sarah Payne, eight, (above) was murdered by paedophile Roy Whiting in 2000
News of the World led a campaign to give parents the same rights as in the US
In the US there is full public disclosure about released sex offenders
Megan's Law was inspired by the murder of seven-year-old Megan Kanka by a known paedophile in July 1994
High profile cases such as the murder of eight-year-old Sarah Payne by a known paedophile in 2000 has led the government to review policy on how much information should be disclosed to the public about sex offenders living in the community.
The website has published the details of five missing offenders, giving their names, ages, photograph and where they have gone missing from, but not the details of their convictions.
The five men named on the website are Alexander Colin Dalgleish, aged 30-35, Gordon Stewart, 25-30, Paul Turner (also known as Paul Francis or Geddes), 50-55, Joshua Karney, 25-30, who also goes by five other names, and Kamil Krawiec, 25-30.
The scheme is being run with the Crimestoppers Most Wanted site, which is designed to help track down Britain's most dangerous criminals who are on the run.
Jim Gamble, chief executive of the CEOP Centre, said the Crimestoppers' website had enjoyed "unprecedented" success in tracking down offenders but urged the public to act responsibly.
"Any vigilante activity will be robustly dealt with and is likely to constitute a criminal offence."
Stuart Kuttner, managing editor of News of the World which has campaigned for parents to know if a paedophile lives in their area, welcomed the news.
The website will identify paedophiles who have gone missing
The paper wants Sarah's Law, named after Sarah Payne, and the full public disclosure on released sex offenders as exists in the US.
Megan's Law was introduced there after the murder of seven-year-old Megan Kanka by a known paedophile in July 1994.
But crime experts said the site did not equate to the implementation of a "Sarah's Law" which would mean publishing the details of offenders who were working with authorities.
Paul Cavadino, chief executive of crime reduction charity Nacro, said: "This is completely different from misguided calls for Sarah's Law, which would mean routinely publishing the details of offenders who are under supervision and complying with the registration laws."
The National Society for the Prevention of Cruelty to Children (NSPCC) backed the move and said it could help protect young people.
Phillip Noyes, director of public policy, said: "The NSPCC believes it is right that convicted child sex offenders who disappear off the radar and flout the sex offender register are identified on this website."
Campaign group, Mothers Against Murder and Aggression (Mama), also welcomed the plans.
But the group, which also backs proposals for a "Sarah's Law", urged people not to take matters into their own hands.
In 2000, a paediatrician in Newport, south Wales, was forced to flee her house when vigilantes seemingly confused her job title.
A Mama statement said: "There will be those who believe this will make paedophiles 'go underground' but they are already underground and we need to know who is living in our community.
"However, we must have no repeat of the paediatricians being attacked and must not encourage anyone to become a vigilante."
The CEOP site coincides with the first anniversary of the Crimestoppers site, which went live last November, receiving almost 40 million hits and leading to 24 arrests.