PARIS -- French authorities say a man suspected of beheading a businessman at a French gas factory in June has killed himself in his prison cell.

Deputy Prosecutor Jean-Michel Bourles in Evry, a Paris suburb, said Wednesday that Yassin Salhi hanged himself with an electric cable Tuesday night in Fleury-Merogis prison. The former delivery driver faced preliminary murder and terrorism charges and was suspected of ties to Islamic State extremists.

The attack in France's southeast put the country back on high alert after January's deadly extremist attacks against satirical newspaper Charlie Hebdo and a kosher market.

French prosecutors said Salhi lured his boss into a van, knocked him unconscious and beheaded him. Salhi allegedly carried a long-bladed knife, a gun and two brand-new flags emblazoned with the Muslim declaration of faith.