The French government urged calm Monday after the killing of a teenage boy at a village dance party earlier this month was followed up with violent demonstrations by the extreme right. 

The death of the 16-year-old, named only as Thomas, has been seized upon by the far-right who have portrayed the killing as symbolic of increasingly insecure conditions in French society. 

Olivier Veran, the spokesman of President Emmanuel Macron's centrist government, went in person to the village of Crepol in southeastern France where Thomas was killed in a bid to keep a lid on tensions. 

The death of Thomas is "a tragedy that puts us at risk of a tipping-over of our society, if we don't rise to the occasion," he said.

"It's up to the judiciary to render justice. Not for the French public themselves," he warned, while acknowledging that the death of Thomas was the result of more than a "simple fight at a village dance". 

Around 100 extreme-right activists travelled to the nearby town of Romans-sur-Isere on Saturday, a police source said, adding that they were looking for a fight with young people from the La Monnaie neighbourhood, where many suspect the perpetrators of the November 19 killing live. 

A further far-right gathering in Romans was dispersed by police Sunday.

With 24 people held in custody since Friday in connection with the events, senior prosecutor Laurent de Caigny insisted "no one can take justice into their own hands outside the law" and urged people to allow investigators to do their work.

"Those who oppose this by illegitimate violence will answer for it," he added.

- Tensions running high -

Nine people believed connected to the November 19 violence in Crepol were placed under investigation on Saturday for crimes including murder and attempted murder, prosecutors in nearby city Valence said.

Fighting appears to have broken out inside the dance before spilling outside, with a group of suspects arriving by car as the party was ending.

Conservative and far-right politicians have been swift to point to the fight at the village dance as evidence of danger from immigrants and minorities, even as details of the night's events remain unclear.

Prosecutor de Caigny said the violence appears to have broken out for "petty reasons" rather than being a premeditated attack based on "race, ethnicity, nationality or religion" -- perhaps even a passing remark about "somebody's haircut". 

But prosecutors have added that nine of the 104 witnesses interviewed reported hearing hostile language "about white people" during the fight. 

As well as Thomas' death, nine people were wounded in Crepol on November 19, four of them seriously. 

The Crepol incident came with France already on edge, with a surge in anti-Semitic incidents since Hamas' October 7 attack on Israel and the state's bombing and invasion of the Gaza Strip in response.

Last month's killing of a teacher by a Muslim former pupil originally from Russia has also stoked tensions. 

mlm-chp-tgb/sjw/rox