A prison which plays host to a number of Islamist radicals – including the brother of the Toulouse 2012 attack perpetrator Muhammed Merah – has been set ablaze with a dozen injured as prisoners staged a riot after stealing the keys from a prison guard and taking over the complex.

A large scale mutiny which saw 60 prisoners released from their cells broke out Monday afternoon at the Vivonne-Poitiers prison located in the French town of Vienne near Poitier. Le Figaro reports “five members of the security forces and six detainees were hospitalized, one inmate suffered a heart attack”.

According to local reports the inmates were able to take over the building after stealing the keys of one of the prison guards. While prosecutors in Poitiers have claimed that there have so far been no reports of hostages there has been ample evidence via social media that the prison itself has been set on fire.

Local radio station France Blue Poiteu have posted several pictures of the smoke billowing from the building, and several videos via their Twitter account in which they claim that the screams of prisoners can be heard as huge columns of thick black smoke comes from the prison complex itself indicating that many may be trapped inside.

Emmanuel Giraud, regional delegate of the FO union prison for New Aquitaine has said, “the detainees were able, in circumstances still undetermined, to steal the keys of a supervisor keychain, which allowed them to open the cells. They set fire to all corridors of a floor.”

Authorities say that the perpetrators are still inside the building on the second floor. The prison building holds around 180 inmates and now over 150 armed French police have been dispatched to the scene to try and restore order along with fire brigade units to put out the blaze.

The current motivation for the riot and the arson of the complex is so far unknown, but the fact the prison is known as a place of Islamist radicalisation will spark concerns.