Two were made in the name of the Armed Islamic Group (GIA), the most ruthless of Algerian fundamentalist groups and the one responsible for hijacking an Air France Airbus last Christmas. The other came from an unknown organisation calling itself the Algerian Islamic Jihad.
The first GIA claim was made in a newsletter, el-Ansar, (The Partisans), distributed outside a mosque in Stockholm yesterday. The second was a telephone call to radio station, RTL in Paris, on Thursday evening, simply claiming responsibility.
The third, on behalf of Algerian Islamic Jihad, was made yesterday to the France Inter radio station in Paris. The call, traced to Frankfurt, was made by someone with a North African accent, and said "our envoy has returned safe and sound to Germany, his land of exile, after accomplishing his mission successfully". The caller warned that for every "Islamist" killed, one French person would be killed "on French territory". No other European country would be affected.
Seven people were killed and more than 80 injured in the blast during the evening rush hour at Saint-Michel station.
One result may be effectively to annul the Schengen agreement on the abolition of border controls in Europe. France, which postponed final implementation of the agreement until January because of "practical problems", reinstated most of its border controls immediately after the bombing, and there is strong pressure to keep the controls indefinitely.
If there is any substance in the GIA claim from Frankfurt, this would only confirm French suspicions that the stricter external border controls, are not effective. It might become impossible for any French government to implement Schengen fully.