After more than three weeks of extreme caution, the French authorities are finally conceding that recent attacks in Paris are the work of a single terrorist cell belonging to the Armed Islamic Group, the GIA. Known as the most ruthless of Algeria's fundamentalist organisations, the GIA was responsible for the hijacking of an Air France Airbus last Christmas and lost four of its men when French troops stormed the plane at Marseilles.
Evidence gathered by the police and communicated by "well-informed sources" to journalists over the weekend is said to link the group conclusively not just to the Saint-Michel Metro bombing on 25 July and the bomb near the Arc de Triomphe last Thursday, but also to the assassination of a Muslim cleric, Imam Abdelbaki Sahraoui, at a mosque in northern Paris on 11 July.
The imam was a member of the Algerian Islamic group FIS and is believed to have been used as an intermediary by the French government in attempts to encourage dialogue between the Algerian military government and Islamic groups. He had received many death threats from the GIA, which split from the FIS in 1991 over its decision to take part in elections.
It has been revealed, too, that the RTL radio station in Paris received a call on Friday evening, the day after the Arc de Triomphe bomb, from someone admitting responsibility in the name of the GIA "high command". According to RTL, the call was identical to one it received on the day after the Saint-Michel bombing.
Other links established between the three attacks include the timing - early evening - the type of bombs used, and an individual identified by witnesses as having been at the scene of two of the attacks.
The bombs were both contained in Belgian-made camping gas cylinders, filled with a mixture of potassium chlorate and other chemicals. This is said by experts to be almost a signature of the GIA. According to information released only now, a gas cylinder of the same type apparently was found in a hold-all left near where the imam was killed. The cylinder was traced to a DIY store in south-eastern Paris. Whoever bought the cylinder also bought a voltmeter, batteries, cable and soldering equipment.
There is also a mysterious man of North African appearance who was seen by witnesses both at the scene of the imam's killing and shortly before the Saint-Michel bombing. The man is not believed to have been directly involved in either attack, in the sense of having fired the shots or planted the bomb, but could have been present in some sort of supervisory or look- out role. Police are not saying whether he is one of the the three men whose photofit pictures were distributed last month.
The reluctance of the authorities to pin the attacks officially on the GIA so far may be explained in part by their fear of closing off other avenues of inquiry, and their concern not to exacerbate already tense relations with parts of the North African community.
None the less, there is evidence that the French authorities were braced for possible GIA attacks from mid-June, when they are said to have been tipped off by the Algerian authorities that a commando cell was on its way to France from Algeria.
According to the Nouvel Observateur magazine, it was this information which prompted a nationwide round-up of more than 140 people on 20 June. All were suspected of having links to the GIA on the basis of a massive undercover operation conducted by French police in previous months.
Despite the round-up, however, the Algerian Tribune newspaper reported on 1 July that GIA commandos had reached France and were operational. It said they had a "hit list", which included Imam Sahraoui, and warned of indiscriminate bomb attacks to avenge the four deaths at Marseilles. The imam was killed 10 days later, and the Saint-Michel bombing took place two weeks after that.
If the GIA was the favoured suspect all along, the precise motive for the Paris attacks has been harder to discern. Some specialists are suggesting that the action is more than an act of revenge for Marseilles, and more than a warning to a new French president and government that the GIA is not to be ignored. They argue that at least some GIA cells are "used" by elements of the Algerian military government in cases where their interests coincide.
At present, they say, the Algerian military has as great a stake as the GIA in ensuring that elections planned for the autumn do not happen: and they both want to convince France of the risks.