Attackers have daubed swastikas on 15 Muslim graves at a military cemetery in Strasbourg, northeast France.
Interior Minister Dominique de Villepin condemned the attack, which happened overnight and which comes after a string of attacks against Jewish, Muslim and Christian property in the region.
Some 300 graves have been desecrated in recent months.
Rector Abdellah Boussouf, of the Strasbourg mosque, demanded more forceful government action. "I can no longer be content at this stage with the condemnations and pledges of solidarity of political rulers. I want results," he told reporters.
"France's Muslims as a whole have the feeling they are considered second-class citizens," he added.
A desecration of Muslim graves in Strasbourg in June prompted French President Jacques Chirac to announce a new drive to end ethnic intolerance in France.
Mr de Villepin visited local Muslim leaders after that attack to announce the creation of an interfaith committee to work towards greater tolerance and understanding.