Images recently appeared on the social network site Twitter claiming to show an adult Jon Venables, who was released from jail on licence with a new identity in 2001.
The Attorney General said court papers will be served shortly to bring contempt proceedings against those who posted the pictures, which have since been taken down.
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The former reality TV star will follow in the footsteps of Abraham Lincoln and John F Kennedy when he takes his oath later on Friday.
The President-elect's comments on Twitter will come under even closer scrutiny when he takes office on Friday.
Cold, quiet and calm