UPDATE, 11:30 AM: French President François Hollande just addressed the nation live on television, declaring tomorrow a national day of mourning in the wake of today’s mass killing at the headquarters of satirical weekly Charlie Hebdo. Flags on public buildings will fly at half-mast for three days, Hollande said, as he condemned the “cowardly” attack which left 12 dead and 11 seriously injured. Of the victims, he said, “Today, they are our heroes.” The shootings took place this morning during Charlie Hebdo’s editorial meeting. France was attacked “at its heart,” Hollande said.