A woman was beheaded by an attacker with a knife who also killed two other people at a church in the French city of Nice on Thursday, police said, in an incident, the city's mayor described as terrorism.

Mayor Christian Estrosi said the knife attack had happened in or near the city's Notre Dame church and that police had detained the attacker.


Police said three people were confirmed to have died in the attack and several were injured. A police source said a woman was decapitated. French politician Marine Le Pen also spoke of a decapitation having occurred in the attack.

The French police described the scene as a "vision of horror". Estrosi said a woman victim had been decapitated but he had no details of how the two others were killed.

Enough is enough: Mayor Christian Estrosi

"We have two people killed inside the church ... and a third person who was in a bar facing the church where she had taken refuge. Enough is enough ... we have to remove this Islamo-fascism from our territory", the Mayor added.

The incident comes two weeks after the horrific killing of 47-year-old teacher, Samuel Paty, by a refugee Islamist terrorist after cartoons of Prophet Mohammed were shown by Paty to his students in a class on freedom of speech.

"Before it was a school professor, this time the Islamo-fascist barbarism chose to attack inside a church. Again, it is very symbolic," Estrosi added.