PARIS — A Paris court on Wednesday jailed an Algerian man for 28 years after convicting him of attempted terrorist murder for attacking police guarding Notre Dame Cathedral with a hammer in 2017, crying: “This is for Syria!”

The assault by Farid Ikken, now 43, outside one of France’s most-visited monuments came after a string of Islamic extremist attacks around France in 2015-2016, and was among multiple violent acts targeting security forces.

In the Notre Dame incident, one police officer was lightly injured, and Ikken — a former doctoral student — was shot and wounded by officers. At least 600 people were trapped inside the 12th century cathedral while police secured the surrounding streets and combed the pews.

At the time prosecutors said police found a declaration of allegiance to the Islamic State group in a self-filmed video on his home computer but said the attacker appeared to have acted alone.