Hundreds have turned out in New York City in support of free expression after the deadly terror attack targeting a French satirical publication.

Several hundred people braved freezing temperatures in Manhattan's Washington Square Park on Saturday as a woman danced under a sign that read "Je suis Charlie."

"I am Charlie" has emerged as a rally cry after two shooters killed 12 people Wednesday at the Paris headquarters of the satirical magazine Charlie Hebdo.

Organizers said they were showing solidarity with the French after three days of violence left 20 dead, including three gunmen.

The march came after hundreds of thousands rallied hours earlier in French cities from Toulouse in the south to Rennes in the west to honor the victims.

A massive rally is planned Sunday in Paris.