The five were arrested on Sunday, four of them in the eastern city of Strasbourg, and one in the southern city of Marseille.
Molins said the Strasbourg “commando” of four was plotting a terror act on 1 December but that investigators had not yet determined which was “the specific chosen target among all those considered by the group.”
He said the five men were “given guidance remotely” from an IS member based in Iraq or Syria and that they had a “clear will to find and to identify targets to commit an act in the very short term”.
Investigators found communications of GPS coordinates on one suspect’s USB stick.
The five men, he said, “had common instructions to obtain weapons, instructions given by a person from the Iraqi-Syrian zone through encrypted applications popular among terrorists.”
The four arrested in Strasbourg were two French citizens both aged 37, a 36-year-old Franco-Tunisian and a 35-year-old Franco-Moroccan.
Two of them had been convicted several times in France. The man arrested in Marseille was a 46-year-old Moroccan.
All were detained after a “long-term” investigation by French intelligence services.
The four Strasbourg suspects are long-time friends, seeing each other regularly, “all four communicating in a closed network through a dedicated telephone line,” Molins said. But they weren’t in touch with the Marseille suspect.
After being held in custody for five days, the five were moved at midday to the Paris court house and were to be presented later to counter-terrorism investigating judges.
The Paris prosecutor asked magistrates to hand the five preliminary charges of taking part in a “terrorist criminal association” and to jail them.
The suspects were in possession or in search of weapons and financing, Molins said. Among weapons seized during home searches in Strasbourg were two handguns, two automatic rifles, several cartridge clips and dozens of cartridges of different calibers.
On the USB key, investigators also found instructions for a money handover and detailed explanations to obtain weapons and ammunition.