President Francois Hollande vowed the state would protect French Jews with all its force as he led a ceremony Tuesday at a Jewish cemetery where hundreds of graves were vandalized.
"I know some are asking if they can live in peace in their country, and ask who will protect them against those who wish them harm," Hollande said at the ceremony in Sarres-Union in the eastern Alsace region.
"One more time, I want to give the Republic's response – that it will protect you with all its force."
He was speaking at a Jewish cemetery where some 300 tombs and graves were defaced and damaged last week.
"You get the impression that an army has passed through here," said the chief rabbi of Strasbourg, Rene Gutman, as he visited the cemetery.
Five boys aged 15 to 17 have been taken into custody over the incident.
Prosecutors say there is no indication yet that they were specifically targeting the Jewish community, with one boy reportedly claiming they were unaware the cemetery was for Jews.
But in the current climate – following violence against Jews in Copenhagen this week and last month's jihadist attacks in Paris – the vandalism has leapt to the top of the political agenda. French Jews in particular are feeling increasingly vulnerable after years of steadily rising anti-Semitism.
Hollande, keeping with the resolute tone he has struck repeatedly since the Paris attacks, called the vandalism "an odious act".
"This is not just another incident, another banal act – it is the expression of an idea that corrodes our Republic," said Hollande.
The local prosecutor said Monday the youngest of the suspects came forward to police after being taken aback by the scale of reaction to the vandalism.
France's government has been particularly keen to show it is tackling anti-Semitism in the face of Israel's repeated calls for Jews to emigrate in response to rampant – sometimes violent – anti-Semitism.
"To the Jews of Europe and to the Jews of the world I say that Israel is waiting for you with open arms," said Israeli Prime Minister Binyamin Netanyahu this weekend, repeating a call he made after the Paris attacks, in which four Jews were killed.
The Council of Europe called on France to take firmer action on hate crime as the European rights institution released a report into the issue on Tuesday.
"In recent years, the anti-Semitic, anti-Muslim and homophobic acts have increased greatly. It is vital to stop this phenomenon and punish those responsible," said human rights commissioner Nils Muiznieks.
The government has said it is working on new legislation to tackle hate crimes, which will be tabled in the coming weeks.
Last month, the country's main Jewish group said the number of anti-Semitic acts doubled in France during 2014, with acts involving physical violence leading the increase.
Some 851 anti-Semitic acts were registered in 2014, compared with 423 the previous year, with acts of physical violence jumping to 241 from 105, the association said.
AFP contributed to this report.