A young man of 20 died on Wednesday at the Bordeaux-Gradignan remand center in Gironde.
At the end of the afternoon, his cell caught fire.
His fellow prisoner, aged 37, was seriously injured and hospitalized in absolute emergency in the evening.
It was a supervisor who first smelled a burning smell before realizing that a door to a cell on the fourth floor was hot, specifies France Bleu.
With colleagues, they managed to extract the older of the two detainees before discovering the victim lying on his bed.
The cause of this fatal fire is not yet known.
They were three men to occupy this cell before one of them was moved on Wednesday.
It is far too early to tell if there is a link at this stage of the investigation.
One of the most overcrowded prisons in France
For the prison union FO, prison overcrowding is in question because it is impossible today to ensure the safety of all prisoners.
Today, forty-six French prisons have a density greater than 150%.
It even exceeds 200% in four establishments, including the Bordeaux-Gradignan prison.
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Prisons: More than two detainees for a place in the Gradignan remand center, a symbol of prison overcrowding
An inmate tries to escape during a medical visit to the Bordeaux University Hospital
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