TURKEY-BLAST/(01 of13)
Open Image ModalA police officer stands guard near the site where a Turkish police bus was targeted in a bomb attack in a central Istanbul district, Turkey, June 7, 2016. REUTERS/Osman Orsal (credit:Osman Orsal / Reuters)
TURKEY-BLAST/(02 of13)
Open Image ModalA police helicopter flies over the site where a Turkish police bus was targeted in a bomb attack in a central Istanbul district, Turkey, June 7, 2016. REUTERS/Osman Orsal (credit:Osman Orsal / Reuters)
TURKEY-BLAST/(03 of13)
Open Image ModalPeople remove glass of a destroyed shop window near the site where a Turkish police bus was targeted in a bomb attack in a central Istanbul district, Turkey, June 7, 2016. REUTERS/Osman Orsal (credit:Osman Orsal / Reuters)
TURKEY-BLAST/(04 of13)
Open Image ModalPeople stand beside beside a Turkish police bus which was targeted in a bomb attack in a central Istanbul district, Turkey, June 7, 2016. REUTERS/Osman Orsal (credit:Osman Orsal / Reuters)
TURKEY-BLAST/(05 of13)
Open Image ModalAn armoured vehicle drives near a Turkish police bus which was targeted in a bomb attack in a central Istanbul district, Turkey, June 7, 2016. REUTERS/Osman Orsal (credit:Osman Orsal / Reuters)
TURKEY-BLAST/(06 of13)
Open Image ModalA destroyed van is pictured near a Turkish police bus which was targeted in a bomb attack in a central Istanbul district, Turkey, June 7, 2016. REUTERS/Osman Orsal (credit:Osman Orsal / Reuters)
Turkey Attack(07 of13)
Open Image ModalTurkish police officers work near the scene of a blast after an explosion in Istanbul, Tuesday, June 7, 2016. A car bomb attack targeting a bus carrying riot police during rush hour traffic in Istanbul on Tuesday has killed number of people and wounded dozens others, the city\'s governor said.((AP Photo/Emrah Gurel) (credit:ASSOCIATED PRESS)
Turkey Attack(08 of13)
Open Image ModalTurkish police work at the scene of an explosion in Istanbul, Turkey, Tuesday, June 7, 2016. A car bomb attack targeting a bus carrying riot police during rush hour traffic in Istanbul on Tuesday has killed numbers of people and wounded dozens others, the city\'s governor said. (AP Photo/Lefteris Pitarakis) (credit:ASSOCIATED PRESS)
Large Bomb Blast Hits Istanbul(09 of13)
Open Image ModalISTANBUL, TURKEY - JUNE 7: Police officers secure the area near to the scene of a bomb attack which targeted a police bus in the Vezneciler district on June 7, 2016 in Istanbul, Turkey. At least 7 police officers and 4 civilians were killed with a further 36 people wounded after an explosion, believed to have been caused by a bomb, targeted a police bus in central Istanbul according to Istanbul governor Vasip Sahin. (Photo by Defne Karadeniz/Getty Images) (credit:Defne Karadeniz via Getty Images)
TURKEY-ATTACKS(10 of13)
Open Image ModalTurkish police officers sit near the site of a a bomb attack that targeted a bus shuttle service carrying anti-riot police in the Vezneciler district of Istanbul on June 7, 2016. \nA bomb ripped through a Turkish police bus near Istanbul\'s historic centre, killing seven officers and four civilians in the latest of a string of attacks in Turkey\'s biggest city. / AFP / OZAN KOSE (Photo credit should read OZAN KOSE/AFP/Getty Images) (credit:OZAN KOSE via Getty Images)
TURKEY-ATTACKS(11 of13)
Open Image ModalA man removes glass from a destroyed shop window near the site of a bomb attack that targeted a police bus in the Vezneciler district of Istanbul on June 7, 2016. \nA bomb ripped through a Turkish police vehicle near Istanbul\'s historic centre, killing seven officers and four civilians and adding to security concerns after a string of attacks in Turkey\'s biggest city.The bomb targeted a service shuttle bus carrying officers from Istanbul\'s anti-riot police as it was passing through the central Beyazit district close to many of the city\'s top tourist sites, Istanbul governor Vasip Sahin said in a live statement on Turkish television. / AFP / OZAN KOSE (Photo credit should read OZAN KOSE/AFP/Getty Images) (credit:OZAN KOSE via Getty Images)
TURKEY-ATTACKS(12 of13)
Open Image ModalTurkish special force Police officers secure area around the site of a bomb attack that targeted a police bus in the Vezneciler district of Istanbul on June 7, 2016.\nA bomb ripped through a Turkish police vehicle near Istanbul\'s historic centre, killing seven officers and four civilians and adding to security concerns after a string of attacks in Turkey\'s biggest city.The bomb targeted a service shuttle bus carrying officers from Istanbul\'s anti-riot police as it was passing through the central Beyazit district close to many of the city\'s top tourist sites, Istanbul governor Vasip Sahin said in a live statement on Turkish television.\n / AFP / OZAN KOSE (Photo credit should read OZAN KOSE/AFP/Getty Images) (credit:OZAN KOSE via Getty Images)
TURKEY-ATTACKS(13 of13)
Open Image ModalA Turkish police officer stands guard near the site of a a bomb attack that targeted a bus shuttle service carrying anti-riot police in the Vezneciler district of Istanbul on June 7, 2016.\nA bomb ripped through a Turkish police bus near Istanbul\'s historic centre, killing seven officers and four civilians in the latest of a string of attacks in Turkey\'s biggest city. / AFP / OZAN KOSE (Photo credit should read OZAN KOSE/AFP/Getty Images) (credit:OZAN KOSE via Getty Images)