A retired French surgeon may have raped or sexually abused as many as 349 children over the 30 years of his career, a prosecutor investigating the case said Friday.

This could be France's biggest-ever paedophilia case.

Joel Le Scouarnec, 68, is planned on trial in March for the rape and sexual abuse of four child victims.

The allegations against him three decades he practised in hospitals across central and western France.

Accusations include the rape a six-year-old girl living in his neighbourhood, the rape of a young relative and the sexual assault of another, the abuse of a child patient, and allegations of indecently exposing himself.

After charges were brought against him in these cases, investigators discovered secret diaries in which Le Scouarnec described sex scenes involving many more children.

The children were named, which has allowed the police to track them down to obtain their testimony. This, in turn, has led to additional charges.

Le Scouarnec's lawyers have called the journal entries "fantasies".

Laureline Peyrefitte, chief prosecutor of the town of Lorient in Brittany, northwest France, said on Friday that the number of possible victims now is 349.

Many of the alleged crimes were committed too long ago to be prosecuted.

In total, 229 people have been questioned by investigators. 197 of them have pressed charges, Peyrefitte said, adding the case was made "extraordinary" by the way the alleged crimes came to light and the large number of suspected victims.

Francesca Satta, a lawyer for some of the alleged victims, told AFP that "they remember perfectly well what they endured but never talked about it because they were afraid."

Le Scouarnec was given a four-month suspended jail sentence in 2005 for possession of child pornography.

If convicted on the first set of charges, the doctor risks up to 20 years in jail.

He will be tried in the southwestern town of Saintes from March 13 to 17.

He is currently awaiting trial in prison.