At least two French prison guards were shot dead and three others seriously injured after heavily armed men ambushed a prison van to free an inmate, triggering a major manhunt.
The orchestrated attack, which comes amid rising drug-linked violence across Europe, took place at a toll booth in Incarville in the Eure region of northern France. The unnamed inmate and the attackers escaped, police said.
Interior Minister Gérald Darmanin said a major manhunt had been launched.
"All means are being used to find these criminals. On my instructions, several hundred police officers and gendarmes were mobilized," he wrote on X.
Images on social media showed at least two men in balaclavas carrying rifles circling near an SUV that was in flames. The SUV appeared to have been rammed into the front of the prison van.
Drug crime has spiraled across Europe, which has been flooded with cocaine in recent years. Marseille has been the epicenter of France's gang violence, with a particularly violent war between trafficking clans.
Local media reports named the fugitive inmate as 30-year-old Mohamed A.
A French police source said he was suspected of ordering a murder in Marseille, and had ties to the city's powerful "Blacks" gang.

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