The French authorities are questioning two men detained after vandals desecrated graves at a Jewish cemetery in the city of Lyon.
The attack comes amid concerns about anti-Semitism in France
Swastikas and other graffiti were found on about 60 tombstones and a monument to Jews killed during World War II.
This is the latest in a string of attacks against Jewish cemeteries that have drawn strong condemnation from the Paris government.
The French interior minister called the latest desecration a "disgusting act".
The minister, Dominique de Villepin, expressed his "solidarity with the Jewish community" and pledged to bring the perpetrators to justice.
The two men arrested were found in the cemetery around the time of the attack on Monday.
Prosecutors say they did not have any paint with them.
It is unclear whether the two are being held on suspicion of assisting the vandals or as potential witnesses.
"It is very symbolic to see graves that bear the Star of David defaced by a swastika," Lyon Chief Rabbi Richard Wertenschlag said after visiting the cemetery.
"It's an indescribable shock," he added.
The desecration is the latest in a string of similar incidents in France.
More than 300 graves have been defaced in the east of the country since April.
Many attacks occurred at Jewish cemeteries - but Muslim and a Christian graves have also been targeted.
Rising anti-Semitism, often blamed on members of France's five-million-strong Muslim community, is a sensitive issue.
Last month Paris reacted angrily to a call by Israeli Prime Minister Ariel Sharon urging French Jews to emigrate to Israel to escape "the wildest anti-Semitism".