Syrian Passport Found at Scene of Paris Attacks Belonged to Refugee Who Traveled to EU Through Greek Islands

— -- A Syrian passport found on the body of one of the attackers from Friday night's devastating six-part attack in Paris belonged to someone who had crossed into the European Union as a refugee, through the Greek island of Leros, in October, a Greek official told ABC News.

In a statement on the Ministry’s website, Citizen Protection Minister Nikos Toskas said, "The passport holder had passed from Leros on Oct. 3. where he was identified based on EU rules. ... We do not know if the passport was checked by other countries through which the holder likely passed."

The passport was found at the Stade de France stadium, one of the six attacked sites that left a total of 129 killed, including an American college student.

French President Francois Hollande’s has blamed ISIS for the attack, and United States intelligence hasn't seen any information that contradicts Hollande's assessment, U.S. officials said.

Secretary of State John Kerry said from Vienna today that "Daesh [ISIS] has claimed responsibility" for the attacks. And while "we are still gathering information," Kerry said, "we have seen nothing that leads us to a different conclusion."

Hollande said 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.”

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