France's SNCF state railway has received bomb threats from an unknown group demanding €4 million and has already found one explosive device under its tracks, officials said this morning.
The group, which calls itself AZF after a chemical factory in southwestern France that exploded in 2001, has been in telephone contact with police, said Mr Michel Gaudin, director general of the national police force.
Mr Gaudin ruled out any connection to Islamic or Chechen militant groups, telling LCI television: "That is not our working hypothesis at the moment."
The Interior Ministry confirmed it had received several letters from the group and that two investigating magistrates specialising in terrorist cases had launched a judicial probe into the case.
The ministry statement, issued late last night, said it was trying to contact the group and urged the media "to be discreet to not hinder these contacts."