Three people have been killed in a knife attack in the French city of Nice, police say. French anti-terrorism prosecutors are investigating a knife attack at a church in the Mediterranean city of Nice that killed three people and wounded several others at a time when French authorities are on high alert for extremist violence. 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”. The suspect was detained shortly after the attack. Mr Estrosi spoke of “Islamo-fascism” and that the suspect had “repeated endlessly ‘Allahu Akbar’ (God is greatest).” France’s national anti-terror prosecutors have opened a murder inquiry.