People go through a security checkpoint to attend a Mass in homage to victims of the Paris terror attacks at Notre Dame cathedral in Paris on Sunday, November 15. French President Francois Hollande declared a state of emergency after the attacks in Paris on Friday, November 13, and said border security has been ramped up. The terrorist group ISIS claimed responsibility for the attacks.
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French Prime Minister Manuel Valls, center, speaks with police forces with French Interior minister Bernard Cazeneuve, left, and Defence Minister Jean-Yves Le Drian at the Gare du Nord railway station in Paris on November 15 about security measures after the attacks.
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French police secure the perimeter after panic broke out among mourners who paid their respects at the attack sites at restaurant Le Petit Cambodge and the Carillon Hotel in Paris on November 15.
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Mounted police officers patrol in front of the Eiffel Tower in Paris on November 15.
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Security personnel inspect vehicles at the border between Belgium and France on Saturday, November 14.
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A police officer stands guard outside the Cafe Bonne Biere in the Rue de la Fontaine au Roi in Paris on November 14.
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A French police officer guards the French-Italian border on November 14 in Menton, France.
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Soldiers from the 3rd Marine Infantry Parachute Regiment of Carcassonne arrive at Charles de Gaulle Airport in Paris as security reinforcements on November 14.
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Soldiers patrol the Eiffel Tower on November 14.
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French police check vehicles on the bridge between Strasbourg and Kehl, Germany, on November 14.
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Police vehicles are parked near the entrance to the Louvre in Paris on November 14. Interior Minister Bernard Cazeneuve said the state of emergency in France could mean restrictions on people's movements. Airports in France remained open, and airlines were still flying there, though some airlines reported canceled flights.
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French police check vehicles on the so-called European bridge between Strasbourg and Kehl, Germany, on November 14.
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Police stand guard at a train station in Paris on November 14.