Any members of the public revealing the identity of Soldier F may be held in contempt of court, the Attorney General for Northern Ireland has warned.
It comes after the PSNI removed posters in Londonderry allegedly revealing the identity of the Bloody Sunday paratrooper.
Despite a court order banning the naming of the former solider, posters were placed around the city on Saturday, including Guildhall Square, while they were also shared online.
The PPS decided not to prosecute the former soldier in connection with killings during Bloody Sunday in 1972.
Soldier F was accused of murdering James Wray and William McKinney on January 30 1972, when soldiers opened fire on civil rights demonstrators in the Bogside area of Londonderry, killing 13 people.
The ex-paratrooper was also accused of the attempted murders of Patrick O'Donnell, Joseph Friel, Joe Mahon and Michael Quinn.
Soldier F was granted anonymity during the 1972 Widgery Inquiry into Bloody Sunday and last month, a court ruled that he should be allowed to retain anonymity.
In a statement, the office of the Attorney General, Brenda King, said her attention has been drawn to the publication of posters and a series of postings on social media platforms purporting to identify Soldier F.
“Soldier F is the subject of, and he has the protection of, an Anonymity Order made by the Magistrates’ Court,” read the statement.
“The order was made on September 18, 2019, and then, after legal challenge, was maintained on June 21, 2021.
“Any members of the press seeking to report on this matter, and any member of the public posting on social media, should be aware that this court order remains in place, and nothing should be published which identifies (or is capable of identifying) Soldier F.
“A breach of the above court order may constitute a contempt of court.”