French police have detained eight more suspects in connection with the terror attack in Nice, prosecutors said Tuesday, as investigators broadened their search for a possible network behind the assault.
The eight men had links to either 31-year-old Mohamed Lahouaiej Bouhlel–who drove a 19-ton truck through a Bastille Day crowd, killing 86 people–or to a friend of his who has been in custody since July as part of the investigation, a spokeswoman for the French antiterror prosecutor said.
Police detained the eight, a mix of Tunisian and French nationals, in a series of raids Monday across the French Riviera region that includes Nice. In a terrorism investigation, police can keep suspects in detention for questioning for up to 96 hours before filing preliminary charges against them.
Authorities initially suspected that Lahouaiej Bouhlel had been recently radicalized. The investigation later uncovered evidence that Lahouaiej Bouhlel conspired with several others, planning the assault for months.
France’s fight against Islamic State is testing the country’s criminal justice system as an unprecedented number of militants from Islamic State territory return home from Syria and Iraq. The influx has exacerbated overcrowding in French prisons, making them fertile ground for recruitment. Many convicted terrorists use their jail time to groom petty criminals for jihad missions in Iraq, Afghanistan and Syria–or attacks at home.
On Tuesday, French Justice Minister Jean-Jacques Urvoas announced plans to build up to 16,100 new prison cells by 2025.