French Interior Minister Bernard Cazeneuve called on patriotic Frenchmen and women to join up with the police reservists following the attack on the Mediterranean resort of Nice.
"I want to call on all French patriots who wish to do so, to join this operational reserve," Cazeneuve said.
Everyone who wanted to join the reservists would be able to, Cazeneuve said on Saturday.
There are currently 12,000 reservists in France recruited from the gendarmerie, a paramilitary force at the national level charged with police duties, and from the regular police.
Cazeneuve envisages that the reservists could be mobilized at short notice to provide security at locations and events within police districts.