A convicted sex offender has begun a legal case in the Belfast High Court to force Facebook to remove a page set up to monitor paedophiles in Northern Ireland.
The man, who cannot be identified, is also seeking an injunction to stop his photograph and details from appearing on the social networking site.
He is currently out on licence after serving a prison sentence for sexual offences.
Following his release, he discovered that his photo and threatening comments had been posted online.
He wants Facebook to terminate the accounts of anyone operating the page.
Facebook has already removed the man's photograph and comments made about him, but a lawyer for the company said the further relief being sought by the plaintiff was neither necessary nor proportionate.
The judge is to hear full arguments in the case from both sides later this week.