France attack: Deadly stabbing in Nice 'is terrorism', says mayor
The mayor of Nice says a suspect has been arrested after the attack at the Notre-Dame basilica.
Nice Mayor Christian Estrosi said there had been a "terrorist attack at the heart of the Notre-Dame basilica".
One elderly victim who had come to pray was "virtually beheaded". A suspect was shot and detained shortly afterwards.
Mr Estrosi spoke of "Islamo-fascism" and said the suspect had "repeated endlessly 'Allahu Akbar' (God is greatest)".
President Emmanuel Macron has arrived in the southern city and is meeting police officers at the scene of Thursday's attack. Anti-terror prosecutors have opened a murder inquiry and France raised its national security alert system to its highest level.
Mr Estrosi compared the attack to the recent murder of teacher Samuel Paty, who was beheaded close to his school outside Paris earlier this month.
Police have not suggested a motive for the attack in Nice. However, it follows days of protests in some Muslim-majority countries triggered by President Macron's defence of the publication of cartoons that depicted the Prophet Mohammed. There have been calls in some countries for a boycott of French goods.