Hollande Calls Attacks an 'Act of War'; Americans Injured

French President Francois Hollande is blaming ISIS for a series of attacks across Paris Friday night that left at least 127 dead and many more injured, including Americans.

Hollande called the attacks "an act of war" in a speech Saturday morning local time. "And when faced with war, the country must take appropriate decisions," he said. "An act committed by a terrorist army, DAESH [ISIS], against what we are, a free country that speaks together with the planet."

Eight attackers are dead, and seven died detonating suicide vests, according to Agence France-Presse, citing police. A Syrian passport was found on the body of an attacker near one of the attack sites, the Stade de France stadium, police told ABC News.

Three hundred people were hospitalized, including 80 in critical condition, according to French news agency AFP.

Americans were among those injured, according to the State Department.

"The U.S. government is working closely with French authorities to identify American victims," said Deputy Spokesperson Mark Toner. "We are aware there are Americans among the injured, and are offering them the full range of consular assistance."

Hollande says the attacks were prepared and planned with outside complicity.

"An act of war prepared, planned, from outside, with outside complicity which an investigation will establish," Hollande said. "An act of absolute barbarism. In this painful period, so serious, so decisive for our country, I appeal for unity, for togetherness, for cool-headedness, and I will address Parliament in a joint session at Versailles on Monday."

ISIS today released a statement claiming responsibility for the attack. In an audio statement released online in Arabic and French, the group said ISIS "soldiers" targeted the "capital of prostitution and obscenity."

The statement said eight attackers were involved and claimed the attack was the "first of the storm and a warning to those who wish to learn."

Secretary of State John Kerry said, "these kinds of attacks are the most vile, horrendous, outrageous, unacceptable acts on the planet."

"So we are witnessing a kind of medieval and modern fascism at the same time," Kerry said. "Which has no regard for life, which seeks to destroy and create chaos and disorder and fear. And the one thing we can say to those people is what they did in this is stiffen our resolve. All of us to fight back, to hold people accountable and to stand up for rule of law which is exactly what we're here to do."

In the wake of the attacks, Hollande has declared three days of national mourning and the French flag is flying at half-mast on top of the Elysee palace.

Security is also tightening around the city.

The management of the Eiffel Tower has decided to close the attraction indefinitely, AFP reported.

All public buildings in Paris, including schools, museums, libraries and town halls, were closed indefinitely starting Saturday. An additional 1,500 soldiers were mobilized to guard Paris's parliament buildings, religious sites and tourist attractions. Police said public demonstrations are banned in the Paris area until Thursday.

The Associated Press contributed to this report.

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