The 28-year-old detainee was taken to hospital on January 25 in cardiovascular arrest, before dying there on February 2.
He had been "mastered" by several supervisors during an incident at Meaux prison.
A judicial investigation for willful violence by a person holding public authority and violence resulting in death without intention of giving it was opened after the death in early February of a prisoner of Meaux, said Thursday the prosecutor of the city, confirming information from the
Parisian
.
On January 25, Jimony Rousseau, a 28-year-old inmate, was taken to hospital for cardiovascular arrest after being "overpowered" by guards during an incident.
He died there on February 2, eight days later.
A first judicial investigation had been opened for "research of the cause of death".
"Intentional violence has probably been committed"
"It results, in particular from the hearing of three supervisors, that voluntary violence was probably committed on the person of Mr. Rousseau during his arrest", declared Thursday the prosecutor of the Republic of Meaux, Laureline Peyrefitte.
His autopsy had concluded "the existence of cerebral edema due to prolonged cardiac arrest".
"At this stage of the case, the causal link between the violence and the death of Jimony Rousseau has still not been established. This is what the investigation will have to determine. In particular, additional forensic analyzes must be carried out", she added.
The Minister of Justice Eric Dupond-Moretti, for his part, ordered an inspection in order to "shed light on this affair".