A French counterterrorism source told Insider that the attacker shouted about cartoons on Thursday before the killings.
Violence in France
An attacker beheaded a woman in Nice, France, on Thursday morning — one of three people killed inside a church. The attack came weeks after the similar murder of a teacher in Paris who had shown his class images depicting the Prophet Muhammad. Tensions continue to rise between French President Macron and global Muslim community.
The most recent violence took place at nice's notre-dame church
Christian Estrosi, the city's mayor, said on Twitter that the attacker had been arrested and one of the people killed was a church warden.
The victims were identified as Vincent Loquès, the church sexton, Simone Barreto Silva, a care worker and worshipper, and an unnamed 60-year-old woman.
France's anti-terrorism prosecutor said the suspect arrived on the Italian island of Lampedusa on September 20 before going to mainland Italy and later France.
The attack in Nice followed the murder of Samuel Paty, a teacher in Paris
The 47-year-old history teacher showed his pupils caricatures of the Prophet Muhammad from the satirical newspaper Charlie Hebdo as part of an obligatory "moral and civil education" course.
The violence is fueling tensions between Macron and Muslim, Arab leaders
Macron is preparing to introduce a new law in December which would give the French government powers to monitor and regulate mosques and Islamic communities.
Arab countries including Kuwait, Jordan, and Qatar threatened to boycott French goods in response.
Erdogan has vocally condemned Macron's recent attacks on Islam, saying the French president needed "mental" treatment.
French Muslims and anti-racism activists worried about a rise in hate crimes as a result of diplomatic tensions and new Charlie Hebdo row.