People march down Boulevard Voltaire from the Place de la Republique to the Place de la Nation in Paris on Sunday, January 11. An estimated 1.5 million people joined world leaders in the "unity rally."
Demonstrators hold a sign that translates as "Urgent: More democracy everywhere against barbarism."
Demonstrators wave flags on the monument at the center of the Place de la Republique before the rally.
Charlie Hebdo cartoonist Renald "Luz" Luzier, left, speaks to Charlie Hebdo journalist Patrick Pelloux during the rally. Luzier is the only surviving cartoonist left at the magazine.
European Commission President Jean-Claude Juncker, from left, Israel's Prime Minister Benjamin Netanyahu, former French President Nicolas Sarkozy, Mali's President Ibrahim Boubacar Keita, French President Francois Hollande, Germany's Chancellor Angela Merkel, Palestinian Authority President Mahmoud Abbas and Italy's Prime Minister Matteo Renzi walk together as they lead thousands of people during the rally.
The massive crowd at the Place de la Republique is seen from above.
People gather at Place de la Nation in Paris.
A young man waves a French national flag in the streets of Paris.
Demonstrators make their way along boulevard Voltaire during the rally.
Luzier, center with mustache, marches with other survivors of the Charlie Hebdo massacre as well as family members of victims.
A banner attached to a house overlooking the Place de la Republique reads "Freedom" as thousands of people gather below.
A demonstrator holds up an oversized pencil, a symbol of freedom of expression, beside a banner showing solidarity with Charlie Hebdo, the magazine where 12 people were killed last week.
British Prime Minister David Cameron, second from right, stands with other world leaders during the rally.
A crowd gathers at the Place de la Republique before a massive unity rally in Paris on January 11.
Demonstrators gather in the Place de la Republique before the rally on January 11.
A man and boy watch people gather for the rally from a balcony near the Place de la Republique.
A police officer keeps watch over the Place de la Republique before the rally.
French President Francois Hollande hugs German Chancellor Angela Merkel as she arrives at the Elysee Palace before the rally.
People gather before the rally.
A police officer keeps watch before the rally.