The Islamic State jihadist group claimed gun and bomb attacks in Paris that left more than 128 people dead in a statement posted online on Saturday.
It said "eight brothers wearing explosive belts and carrying assault rifles" conducted a "blessed attack on... Crusader France."
French President Francois Hollande also blamed the Islamic extremist group and called the coordinated assault on Friday night at six different sites an "act of war".
The multiple attacks across the city late Friday were "an act of war... committed by a terrorist army, the Islamic State, against France, against... what we are, a free country," Hollande said.
Gunmen and bombers attacked restaurants, a concert hall and four other locations across Paris on Friday, killing over 120 people.
It was the worst such attack in Europe since the Madrid train bombings of 2004, in which 191 died.