PARIS - Quiet and bespectacled, Christian Ranucci was a passive young man, even on the day of his execution.

In the pre-dawn hours of July 28, 1976, as a mob of of reporters and photographers waited outside, the 22-year-old was woken at his cell in Marseilles Les Baumettes Prison.

Refusing the final rituals - the glass of rum, the offer of a priest and a last cigarette - the young man went to the guillotine with a lamb-like acquiescence. His final words to his lawyer were: "Clear my name."

Thus Ranucci was beheaded. And for a brief while, the tabloids exulted that punishment had been exacted for the death of Maria-Dolores Rambla, an 8-year-old girl who had been abducted from a Marseilles housing estate in June 1974. Her body, stabbed 15 times and bashed with rocks, was found dumped in a creek.

But little by little, the worm of doubt worked its way into the certainty that Ranucci was guilty. A crusading writer, Gilles Perrault, dug out a mass of flaws about Ranucci's interrogation, found gaps or anomalies in the evidence against him and in the conduct of the trial. Perrault's best-selling book, Le Pull-over Rouge was turned into a film of the same name, and they helped to destroy the death penalty in France.

Only two more men were guillotined before President Francois Mitterrand scrapped capital punishment in September 1981 in one of his first acts in office.

Today, nearly 30 years after Ranucci made his walk to the guillotine, the controversy has stirred anew.

And the astonishing implication is that Rambla's murderer is a man now facing trial for one of Europe's most notorious strings of killings.

Not only that: he coolly attended Ranucci's trial, and watched as the young man was convicted and sentenced to death.

The new lead comes from Belgian police who are probing the past of Michel Fourniret, a woodcutter from Belgium's Ardennes region.

Fourniret, 63, is being held in France on charges of killing seven girls and raping or attempting to rape three others, in a long trail of horror on both sides of the border.

Belgian investigators believe Fourniret went on holiday in the Marseilles region every year from 1970 to 1974 - the year that Rambla was killed. He also had a Peugeot 304 - a car almost identical to Ranucci's Peugeot 304.

The rear of both vehicles is very similar to the Simca 1100, the model of car implicated by two witnesses who said that the driver of this vehicle, on the day of Maria-Dolores's abduction, tried to coax children to get inside. The driver of this car wore a red pull-over that was later found by a roadside; the garment was several sizes too small for Ranucci, according to Perrault.

But, the Brussels daily Le Soir reports, the most remarkable find has been the discovery of a photo, taken by a Marseille press photographer at the Aix courthouse in March 1976. There, among the crowd, is a bearded man with glasses said to bear an uncanny resemblance to Fourniret.

French prosecutors say they will diligently follow both tips. But their initial response is scepticism about whether Fourniret was in southern France at the key date; they say they have yet to see the photo; and they note that the method of Rambla's murder was different from Fourniret's preferred style - strangulation.

Perrault predicts calls for the Ranucci case to be reopened wouldn't get very far.

"I can't see the police jumping up and down with enthusiasm about the prospect of delving into an inquiry which was botched by the Marseille police at that time. And don't forget that a President [Valery Giscard d'Estaing] who is still alive refused to issue a reprieve and Ranucci was sent to the guillotine. In my opinion, there will be a big temptation to drop it."