Explosives found in Paris after warning

French President Nicolas Sarkozy, speaking in the eastern French city of Strasbourg, urged caution, but said France would not negotiate with terrorists. "At this point in time I would call on everyone to be very prudent and very measured," he said.

The tip-off was sent by letter to a French news agency, Agence France-Presse, warning that several bombs had been planted in the Printemps department store on the Boulevard Haussmann, which is normally packed with Christmas shoppers at this time of year.

Police said there was no mention of Islam in the letter, adding that recent attacks in Europe tied to Iraq and Afghanistan had been launched without specific prior warning.

The letter, posted from Paris on Dec. 15, said one of the devices was in the cistern of a lavatory on the third floor of the store, but did not say where the other bombs were hidden. Police said their searches had uncovered explosives in lavatories on the third and second floor of the men's section of the huge Printemps store.

Troops in Afghanistan
"The explosives had not been primed which indicates there was no risk of explosion," said Interior Minister Michele Alliot-Marie, adding that the material was "relatively old".

France has more than 2,600 troops stationed in Afghanistan fighting Taliban forces. Last month, a militant group warned in a video aired on Al Arabia television that it would attack Paris if the French soldiers were not repatriated. France was hit by bomb attacks against stores, markets and underground metro stations several times during the 1980s and 1990s, with Algerian or Middle Eastern militants often claiming responsibility.