Attacks have been carried out on several prisons in France, which involved weapons being fired and vehicles set on fire, the country's justice minister said on Tuesday.
On Monday night, the entrance to a prison in Toulon was shot at with an automatic weapon, while vehicles were torched in the car parks of several prisons, according to various French media reports and posts shared on social media.
In addition to Toulon, prisons were reportedly targeted in Aix-en-Provence and Marseille, Valence and Nîmes, Luynes, Nanterre and Villepinte.
France's Justice Minister Gérald Darmanin wrote in a post on X that prisons had faced "intimidation attempts", and said he was going to Toulon to support affected officers.
"The French Republic is facing up to the problem of drug trafficking and is taking measures that will massively disrupt the criminal networks," he added.
A source close to the case told French media that the attacks appeared to be coordinated and "clearly linked to the minister's anti-narcobanditry strategy".
The French government in February launched a new campaign against drug trafficking, vowing to tackle rising gang violence and deaths linked to growing cocaine imports.
In a post on X on Tuesday, France's prison guard union, FO Justice, shared its "deepest concern and anger" following the "extremely serious" attacks overnight.
The union demanded "a strong, immediate, and unambiguous response from the state".
Interior Minister Bruno Retailleau has asked local administrations in France to "immediately strengthen the protection of officers and institutions" following the attacks.
"The state's response must be relentless," he wrote on X. "Those who attack prisons and their officers deserve to be locked up in those prisons and monitored by those officers."
