A number of Twitter users who posted photos claiming to show James Bulger's killer Jon Venables are facing the risk of jail after Britain's top legal adviser launched legal proceedings against them.
Attorney General Dominic Grieve said court papers would be served against a number of individuals.
Venables was 10 when he and classmate Robert Thompson abducted and murdered two-year-old James in Liverpool in February 1993.
The pair were jailed for life but were released in 2001 under the protection of a court order banning any publication of information that could lead to their identification.
Under the terms of an injunction, publication of any image or information purporting to identify anyone as Venables or Thompson is prohibited.
The terms of the order mean that if a picture claims to be one of James Bulger's killers, even if it is not actually them, it would breach the order.
The Attorney General's statement said: "There are many different images circulating online claiming to be of Venables or Thompson; potentially innocent individuals may be wrongly identified as being one of the two men and placed in danger.
"Breaches of the order may be a contempt of court punishable by a fine and/or imprisonment.
"It is also a criminal offence to encourage others to commit acts of violence or to publish online malicious communications."
Images recently appeared on Twitter claiming to show an adult Venables, who was released from jail on licence with a new identity in 2001.
Dame Elizabeth Butler-Sloss, of the High Court Family Division, made an unprecedented court order banning publication of any information which could lead to the revelation of their new identities.
Venables, now 30, had his parole revoked in 2010 and was jailed for two years after admitting downloading and distributing indecent images of children.
James's mother Denise Fergus, has always opposed the injunction, fearing it could lead to innocent men being accused of being James's killers.