PARIS, March 16: French Prime Minister Jean-Pierre Raffarin received a letter on Tuesday from an unknown Muslim group that threatened to attack France and French interests abroad, triggering an official probe , the justice ministry said.

"A group calling itself 'Servants of Allah, the Powerful and Wise One' today sent the prime minister a message, via Le Parisien newspaper, that included threats against both the national territory and our interests abroad," the justice ministry said in a statement.

Paris prosecutors immediately opened the inquiry upon receiving the message transmitted by the newspaper, turning over the investigation to anti-terrorism police, the ministry said. "It is obviously not yet possible to assess the worth of this message," the ministry noted.

Interior Minister Nicolas Sarkozy said that experts were "in the process of analysing" the threats, which came five days after devastating train bombings in Madrid left 201 people dead.

Sources close to the investigation said the group was until now unknown to French intelligence services, which were in the process of researching the organization.

The two-page letter addressed to Raffarin and containing the threats was delivered to the offices of Le Parisien early Tuesday, the sources said. For its part, Le Parisien said it had received a letter signed "Mosvar Barayev commando". It refused to disclose the contents of the letter.

The signature was similar to Movsar Barayev, the leader of a Chechen commando that took hundreds of people hostage in a Moscow theatre in October 2002. Raffarin has called a meeting of parliamentary leaders on Thursday to discuss "terrorist risks".

Earlier on Tuesday, French President Jacques Chirac said after talks with German Chancellor Gerhard Schroeder: "France is not currently a specific target, but like all democracies, it is not immune from terrorist acts."- AFP