Some 80 graves have been desecrated at a Jewish cemetery in eastern France, local officials say.
The damage was discovered on Tuesday, ahead of nationwide marches against a rise in anti-Semitic attacks.
It occurred at a cemetery in the village of Quatzenheim, on the night of Monday into Tuesday, town hall officials told the franceinfo website.
President Emmanuel Macron has condemned anti-Semitic abuse after a prominent intellectual was targeted.
Police stepped in to protect the philosopher, Alain Finkielkraut, after he was bombarded with insults and anti-Jewish taunts by a group of “yellow vest” protesters in Paris at the weekend.
Several local officials denounced the desecration on social media.
Interior Minister Christophe Castaner has warned that anti-Semitism is “spreading like poison” in the country, with a series of anti-Jewish incidents reported in central Paris last weekend.
These included post boxes featuring a Holocaust survivor’s portrait being vandalised with swastikas.
Jewish groups have also been warning that a rising far right across Europe has been promoting anti-Semitism and hatred of other minorities.
Crime data from Germany released last week revealed that anti-Semitic offences had increased by 10% over the past year – including a 60% rise in physical attacks.
Attacks have been blamed on both the far right and Islamists.