France on Tuesday marked 10 years since an Islamist attack on the Charlie Hebdo satirical newspaper that shocked the country, and led to fierce debate about freedom of expression and religion.

President Emmanuel Macron and Paris Mayor Anne Hidalgo led commemorations by laying wreaths at the site of the weekly's former offices, which were stormed by two masked Al-Qaeda-linked gunmen with AK-47 assault rifles.

Macron and Hidalgo also paid tribute to Ahmed Merabet, a Muslim police officer who was executed at point-blank range near the building in the Bastille area of the capital in one of the most shocking images recorded of the tragedy.

Twelve people died in the attacks, including eight editorial staff, while a separate but linked hostage-taking at a Jewish supermarket in eastern Paris by a third gunman on January 9, 2015, claimed another four lives.

The bloodshed signalled the start of a dark period for France during which extremists inspired by Al-Qaeda and the Islamic State group repeatedly mounted attacks that set the country on edge and raised religious tensions.

"Today is not necessarily sad," Frederica Wolinksi, the daughter of famed French cartoonist and Charlie Hebdo contributor Georges Wolinski. "It's good that 10 years later we can still remember those who died on January 7 so well."

The attack on Charlie Hebdo, carried out in retaliation for the newspaper’s irreverent caricatures of the Prophet Muhammad, ignited fierce global debates about the limits of free expression.

In the days that followed, millions marched in solidarity, brandishing pens and signs declaring, “Je Suis Charlie” (I am Charlie).

But 10 years on, the unity of that moment has given way to deeper divisions. Charlie Hebdo said its research shows that while a majority of French still believe in the fundamental right to caricature, younger generations increasingly criticise satire they see as divisive or insensitive, particularly toward marginalised communities. (AFP/AP)