A woman was beheaded and two others were killed in what police and officials say was a suspected terrorist attack Thursday (October 29) at a church in the southern French city of Nice.
The attacker, who was described as wielding a knife and shouting "Allahu Akbar", was quickly detained after being shot by police.
Police also shot dead a man who threatened passersby with a handgun 150 miles away in Montfavet. He was also shouting "Allahu Akbar", according to media reports.
Thursday's attacks, on the birthday of the Prophet Mohammad, were condemned by the French President Emmanuel Macron who called for unity alongside the nation's Catholics.
The whole nation is and will be by their side, so that religion can continue to be exercised freely in our country, he said.
He added more soldiers would be deployed to protect places of worship and schools.
The French Council for the Muslim Faith called for all today's celebrations to be canceled as a sign of solidarity.
Nice's mayor, Christian Estrosi, said the victims at the Notre Dame church were killed in, quote, "a horrible way."
He described the attack as similar to the killing of Samuel Paty, a French teacher beheaded earlier this month in a Paris suburb by a man of Chechen origin.
The attacker had said he wanted to punish Paty for showing pupils cartoons of the Prophet Mohammad in a civics lesson.
Since the teacher's killing, French officials and politicians - backed by many ordinary citizens - have re-asserted the right to display the cartoons.
That's prompted an outpouring of anger in parts of the Muslim world, with some governments accusing President Macron of pursuing an anti-Islam agenda.
Saudi Arabian State TV reported Thursday that a man was arrested in the Red Sea city of Jeddah after attacking and injuring a guard at the French consulate there.