French prosecutors are investigating the violent murder of a Jewish Holocaust survivor in Paris as a possible hate crime, judicial sources told news outlets Monday.

France is home to Western Europe's largest Jewish population. They have warned of increasing anti-Semitism in the country and criticized authorities for not taking the threat seriously.

Mireille Knoll, 85, was stabbed and burnt to death in her apartment (photo above) last week. Police have arrested two suspects, but they have not yet been charged.

One of the suspects was known to visit her regularly.

The Paris prosecutor's office is investigating whether the killing was "motivated by the real or supposed adherence to a religion," a source told Reuters news agency.

Read more: France's Macron blames state for fueling extremism, vows solutions

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'We are in shock'

French President Emmanuel Macron said on Twitter: "I would like to extend my heartfelt condolences on the appalling crime committed against Mrs. Knoll. I reaffirm my absolute determination to fight anti-Semitism."

French Foreign Minister Jean-Yves Le Drian said it was plausible the crime was motivated by anti-Semitism.

"It reminds us of the fundamental and permanent side of this battle [against anti-Semitism]," he said, speaking alongside Prime Minister Benjamin Netanyahu in a state visit to Israel. He had just visited the Yad Vashem Holocaust Museum.

Chief Rabbi Haim Korsia said in a tweet: "The horror of the crime and the violence of the executioners are identical and reflect the negation of the human face."

Jewish leaders have called for a march in her memory.

"We are really in shock. I don't understand how someone could kill a woman who has no money and who lives in a social housing complex," her son told the Agence France-Presse news agency.

Read more: Taking on racism and hate speech in France

Escape from the Nazis

In 1942 Nazi occupiers rounded up more than 13,000 Parisian Jews and bought them to the Velodrome d'Hiver cycling track. Most of them were murdered at Auschwitz. Fewer than 100 survived.

Knoll escaped the roundup by fleeing with her mother to Portugal.

Series of attacks

Exactly one year ago, the Jewish community in Paris was shocked by the murder of Jewish pensioner Sarah Halimi. For months, authorities disregarded anti-Semitic motives in the killing of Halimi, who was beaten and thrown out her window.

The 400,000-strong Jewish population in Paris has been the target of a series of Islamist attacks. In 2015, 250 Jewish tombstones in eastern France were vandalized just days after four Jews were killed in an attack on a kosher grocery in Paris.

Read more: French kosher market hit by suspected arson attack

aw/cmk (AFP, Reuters, dpa)

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