French President Francois Hollande and other dignitaries held a special ceremony Sunday to honor all those killed by terrorists around Paris in 2015 — a year when the European way of life was targeted time and again with deadly consequences.

Hollande and Paris Mayor Anne Hidalgo, in photo at right, unveiled a plaque in memory of victims at satirical newspaper Charlie Hebdo, a kosher market, a rock concert, cafes, a stadium and elsewhere. The violence left some 150 people dead, and several attackers were also killed. Sunday's ceremony took place at Place de la Republique, a plaza that has become a symbol of Parisians' solidarity since the attacks, which began Jan. 7, 2015, with the Charlie Hebdo attack. French rocker and national icon Johnny Hallyday joined the army choir in a special, somber musical performance. The country has been under a state of emergency after the deadly attacks in Paris on Nov. 13.