Three alleged Islamic radicals have been placed under formal investigation in France for having "connections with a terrorist enterprise".
The three men are suspected of having provided logistical support in an alleged plot to blow up a cathedral in the eastern city of Strasbourg.
Under French law, being placed under formal investigation represents one step short of being charged with a crime.
The three have been in jail since their arrest last week.
The alleged plot to attack Strasbourg Cathedral in December 2000 was foiled after German police discovered video footage of the cathedral and marketplace during a raid on an apartment.
Four people were arrested in Frankfurt, while others suspected of connections with the plot were arrested elsewhere in Europe.