Authorities identified Ibrahim Issaoui as the suspect in Thursday’s at the Basilica of Notre Dame in Nice, France, that left three people dead. Investigators detained five people in Nice and the nearby town of Grasse for questioning over the weekend. Anti-terrorism authorities in Tunisia, where Issaoui is from, opened an investigation into a previously unknown extremist group that claimed responsibility for the attack online. Churches across France prayed for the victims during Sunday services.

What motivated the attack? Issaoui, who is hospitalized in life-threatening condition, carried a Quran into the church. Muslims in countries around the world this week are protesting French President Emmanuel Macron’s refusal to condemn caricatures of Muhammad. A French court is preparing to issue a verdict against suspects in a 2015 attack on Charlie Hebdo after it originally published the offending cartoons. The Islamic State (ISIS) and al-Qaeda have recently called for attacks against France. A Greek Orthodox priest remained in critical condition after a gunman shot him in the French city of Lyon on Saturday. Authorities have not confirmed the motive of the attack as they continue to search for the gunman.

Dig deeper: From the WORLD archives, Mindy Belz’s report in Globe Trot about a 2016 terror attack in Nice that killed 84 people.

Editor’s note: WORLD has updated this report since its initial posting.