The mother of one of the two suspects arrested in the anti-Semitic murder of 85-year-old holocaust survivor Mireille Knoll has been arrested after police suspect she may have attempted to tamper with the weapon used to stab the pensioner to death.

The woman, who is the mother of suspect Yacine M., was arrested and charged with tampering with evidence on Friday but reports of her charges only came to light on Tuesday, broadcaster Franceinfo reports.

According to investigators, the woman lived in the same building as Ms. Knoll, who was stabbed to death and then set on fire in an act that was determined by investigators to have been anti-Semitic in nature.

Two men, one of whom was well-known to the victim for years and had been previously convicted of sexual offences, were arrested and have since proceeded to accuse each other of the murder but both deny the motivation of anti-Semitism.

The murder galvanised public outrage in Paris and saw politicians across the political spectrum condemn the attack and march alongside thousands of others late last month.

Holocaust Survivor Stabbed 11 Times, Set on Fire in Paris Anti-Semitic Killing https://t.co/cyYJfjGYXR — Breitbart London (@BreitbartLondon) March 27, 2018

The Conseil Représentatif des Institutions Juives de France (CRIF), one of France’s leading Jewish community organisations, commented on the murder saying that it “expects from the authorities the utmost transparency in the ongoing investigation so that the reasons for this barbaric crime are known to all as quickly as possible”.

“The terrible thing is that one of the attackers told the other: ‘She’s a Jew, she must have money’,” Interior Minister Gerard Collomb said, and added: “There are stereotypes we have to fight.”

Violence, threats, and intimidation toward Jews in Paris have forced many to move from some of the suburbs surrounding the French capital, which also have significant migrant and Muslim populations.

Jews have also become targets of radical Islamic terrorists. The most well-known case occurred in the immediate aftermath of the Charlie Hebdo attack when Islamic extremist Amedy Coulibaly murdered several Jews in a kosher supermarket in January 2015.

Shortly before the two-year anniversary of the attack this year, two kosher markets in the Paris suburbs of Créteil and Val-de-Marne were defaced with swastika graffiti.