“Our country has been subjected to an Islamist terrorist attack,” the French leader said.
On October 29, three people were killed in an attack on parishioners in a church in central Nice.
According to the mayor of the city, Christian Estrosi, the crime was committed by a "radicalized Muslim".
As Prime Minister Jean Casteks said, the government's response "will be firm, ruthless and immediate."
Two more knife attacks were prevented in Lyon and Avignon, according to media reports.