Photographs of convicted paedophiles who have absconded from supervision in the community could be posted on the internet by a new Home Office agency.
Individual police forces have been approached about the plan
At the launch of the Child Exploitation and Online Protection Centre, director Jim Gamble said he was "working very hard... to make that a real policy".
Negotiations with the Association of Chief Police Officers and individual forces were "well advanced", he added.
But some fear it will trigger vigilante attacks on offenders and look-alikes.
More than 300 of those on the sex offenders' register have lost touch with the authorities at any one time.
About 100 of those are considered to be high-risk offenders, including dozens convicted of offences on children.
But Jo Duncombe, a spokeswoman for RWA, a consultancy that assesses accused child abusers and runs programmes for them and their families, told BBC News the plan could be "very dangerous", triggering vigilante attacks on offenders and look-alikes.
"Clearly we need to find these people, but if there is a case of mistaken identity bad things can happen," she added.
In 2001, 300 parents attacked the home of a taxi driver who had been "named and shamed" as a child abuser by the News of the World.
Elsewhere in the UK, one man was wrongly targeted because he wore a similar neck brace to a known paedophile pictured by the newspaper.
And there was disbelief when a female paediatrician had her house vandalised because of vigilantes' confusion over her job title.
"It is such an emotive subject and anyone who has a child or knows a child who has been abused finds it upsetting," Ms Duncombe told BBC News.
"They are angry and will take it out on anyone they see."
Speaking at the CEOPS launch, Mr Gamble said reformed sex offenders should be allowed to live their lives.
But if they failed to comply with multi-agency public protection panels supervision "it is quite appropriate to do everything in our power to ensure the public is protected and to identify where they are before they target a child in our community".