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A policemen stand as he blocks the street to a cordoned off area after a van ploughed into the crowd, injuring several persons on the Rambla in Barcelona on August 17, 2017. / AFP PHOTO / PAU BARRENA        (Photo credit should read PAU BARRENA/AFP/Getty Images)
PAU BARRENA/AFP/Getty Images
A policemen stand as he blocks the street to a cordoned off area after a van ploughed into the crowd, injuring several persons on the Rambla in Barcelona on August 17, 2017. / AFP PHOTO / PAU BARRENA (Photo credit should read PAU BARRENA/AFP/Getty Images)
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People stand next to flowers, candles and other items set up on the Las Ramblas boulevard in Barcelona as they pay tribute to the victims of the Barcelona attack, a day after a van ploughed into the crowd, killing 13 persons and injuring over 100 on August 18, 2017. 
Police hunted for the driver who rammed a van into pedestrians on an avenue crowded with tourists in Barcelona, leaving 13 people dead and  more than 100 injured, just hours before a second assault in a resort along the coast. / AFP PHOTO / PASCAL GUYOT        (Photo credit should read PASCAL GUYOT/AFP/Getty Images)
PASCAL GUYOT/AFP/AFP/Getty Images
People stand next to flowers, candles and other items set up on the Las Ramblas boulevard in Barcelona as they pay tribute to the victims of the Barcelona attack, a day after a van ploughed into the crowd, killing 13 persons and injuring over 100 on August 18, 2017. Police hunted for the driver who rammed a van into pedestrians on an avenue crowded with tourists in Barcelona, leaving 13 people dead and more than 100 injured, just hours before a second assault in a resort along the coast. / AFP PHOTO / PASCAL GUYOT (Photo credit should read PASCAL GUYOT/AFP/Getty Images)
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A woman gestures as she is escorted out by Spanish policemen outside a cordoned off area after a van ploughed into the crowd, killing 13 persons and injuring over 80 on the Rambla in Barcelona on August 17, 2017.
PAU BARRENA/AFP/Getty Images
A woman gestures as she is escorted out by Spanish policemen outside a cordoned off area after a van ploughed into the crowd, killing 13 persons and injuring over 80 on the Rambla in Barcelona on August 17, 2017.
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A person is helped by Spanish policemen and two men after a van ploughed into the crowd, killing at least 13 people and injuring around 100 others on the Rambla in Barcelona on August 17, 2017.
A driver deliberately rammed a van into a crowd on Barcelona's most popular street on August 17, 2017 killing at least 13 people before fleeing to a nearby bar, police said. 
Officers in Spain's second-largest city said the ramming on Las Ramblas was a "terrorist attack". The driver of a van that mowed into a packed street in Barcelona is still on the run, Spanish police said. / AFP PHOTO / Nicolas CARVALHO OCHOA        (Photo credit should read NICOLAS CARVALHO OCHOA/AFP/Getty Images)
NICOLAS CARVALHO OCHOA/AFP/AFP/Getty Images
A person is helped by Spanish policemen and two men after a van ploughed into the crowd, killing at least 13 people and injuring around 100 others on the Rambla in Barcelona on August 17, 2017. A driver deliberately rammed a van into a crowd on Barcelona's most popular street on August 17, 2017 killing at least 13 people before fleeing to a nearby bar, police said. Officers in Spain's second-largest city said the ramming on Las Ramblas was a "terrorist attack". The driver of a van that mowed into a packed street in Barcelona is still on the run, Spanish police said. / AFP PHOTO / Nicolas CARVALHO OCHOA (Photo credit should read NICOLAS CARVALHO OCHOA/AFP/Getty Images)
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BARCELONA, SPAIN - AUGUST 17:  A damaged van, believed to be the one used in the attack, is surrounded by forensics officers in the Las Ramblas area on August 17, 2017 in Barcelona, Spain. Officials say 13 people are confirmed dead and at least 50 injured after a van plowed into people in the Las Ramblas area of the city.  (Photo by David Ramos/Getty Images)
David Ramos/Getty Images
BARCELONA, SPAIN - AUGUST 17: A damaged van, believed to be the one used in the attack, is surrounded by forensics officers in the Las Ramblas area on August 17, 2017 in Barcelona, Spain. Officials say 13 people are confirmed dead and at least 50 injured after a van plowed into people in the Las Ramblas area of the city. (Photo by David Ramos/Getty Images)
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A person is stretched out of a mall by medical staff members in a cordoned off area after a van ploughed into the crowd, injuring several persons on the Rambla in Barcelona on August 17, 2017.
Police in Barcelona said they were dealing with a "terrorist attack" after a vehicle ploughed into a crowd of pedestrians on the city's famous Las Ramblas boulevard on August 17, 2017. Police were clearing the area after the incident, which has left a number of people injured. / AFP PHOTO / Josep LAGO        (Photo credit should read JOSEP LAGO/AFP/Getty Images)
JOSEP LAGO/AFP/Getty Images
A person is stretched out of a mall by medical staff members in a cordoned off area after a van ploughed into the crowd, injuring several persons on the Rambla in Barcelona on August 17, 2017. Police in Barcelona said they were dealing with a "terrorist attack" after a vehicle ploughed into a crowd of pedestrians on the city's famous Las Ramblas boulevard on August 17, 2017. Police were clearing the area after the incident, which has left a number of people injured. / AFP PHOTO / Josep LAGO (Photo credit should read JOSEP LAGO/AFP/Getty Images)
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Investigators inspect a truck following a shooting incident in New York on October 31, 2017. 
Several people were killed and numerous others injured in New York on Tuesday when a suspect plowed a vehicle into a bike and pedestrian path in Lower Manhattan, and struck another vehicle on Halloween, police said. A suspect exited the vehicle holding up fake guns, before being shot by police and taken into custody, officers said. The motive was not immediately apparent.

 / AFP PHOTO / Don EMMERT        (Photo credit should read DON EMMERT/AFP/Getty Images)
DON EMMERT/AFP/Getty Images
Investigators inspect a truck following a shooting incident in New York on October 31, 2017. Several people were killed and numerous others injured in New York on Tuesday when a suspect plowed a vehicle into a bike and pedestrian path in Lower Manhattan, and struck another vehicle on Halloween, police said. A suspect exited the vehicle holding up fake guns, before being shot by police and taken into custody, officers said. The motive was not immediately apparent. / AFP PHOTO / Don EMMERT (Photo credit should read DON EMMERT/AFP/Getty Images)
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