The death of the 16-year-old, known as Thomas, sparked protests from far-right groups in November.
The mayor of Romans-sur-Isère, in southeastern France, has revealed that she was targetted with death threats following her comments about the death of a schoolboy in a nearby town.
Marie-Hélène Thoraval filed a complaint last week after receiving threats by telephone and social media, including one of death "by decapitation".
The 16-year-old, called Thomas, was fatally stabbed when fighting broke out at a dance in Crépol on 18 November.
An investigation into "organised gang murder" was opened by the local prosecutor, and nine people, including three minors, were arrested and placed under formal investigation.
Speaking on BMF TV, Thoraval called for State "awareness" of the situation in "sensitive neighbourhoods" in the country. She said in particular that Romans-sur-Isère had a problem with "a level of delinquency, which finds its roots in radicalisation" or "drug trafficking".
Thomas' death sparked a series of violent protests organised by far-right groups who alleged a racial motive for the crime.
One march occurred last weekend in Romans-sur-Isère where Thomas had been studying. The town, located 16km south of Crépol, is where extremist groups claimed some of the suspects lived.
Some residents of the Cité de la Monnaie, a district of Romans, called for a demonstration on Saturday to protest against Thoraval's comments to BMF TV.
Other far-fight supporters called for a demonstration in nearby Valence to demand "Justice for Thomas" and to protest against the arrests of violent activists in Romans last weekend.
Ultra-right accounts also posted photos of people they identified as the Crépol attackers on social media, with calls for revenge, particularly in the Monnaie district.
Thoraval explained that the threats she received came in "two stages". On Wednesday two anonymous callers left messages at the town hall calling her a "fascist", and asking her if she "had a Kalashnikov" and "security guards” at her home to defend herself.
In the afternoon she received a private message on Instagram with “a death threat" telling her that she was going to be "decapitated" and that "someone would juggle with my skull,” she said.
Authorities have increasingly called for calm following Thomas' death. In response to the violence, French Interior Minister Gérald Darmanin said he would propose a ban on some ultra-right groups to avoid "a scenario of civil war."