One man died after armed assailants opened fire in an Italian church in Istanbul during Sunday mass in what appeared to be a targetted attack that was swiftly condemned by Pope Francis and Turkish officials.
The Islamic State jihadists claimed responsibility for the attack, the group said via its Telegram channels.
The attack occurred at around 11:40 am (0840 GMT) at the Santa Maria church in the Sariyer district, on the European side of Turkey's largest city.
It was carried out by two masked men, Interior Minister Ali Yerlikaya said on social media.
Turkish officials initially said it looked like a targeted attack against one person rather than against the Catholic church.
The minister said an individual identified only as C.T. -- who was among those attending Sunday's service -- was the target of the gun attack and had lost his life.
Turkish police detained the two suspects as they fled the scene, Yerlikaya announced late on Sunday.
Local officials said around 40 people attended the mass, and suggested that there could have been more casualties.
"After the second shot, the gun didn't work, then they (the attackers) ran. At this moment, everyone lay on the floor. There were around 35 to 40 people inside," Sariyer district's mayor Sukru Genc told reporters.
Istanbul governor Davut Gul said that there had been no other injuries.
'Closeness to community'
Television images showed police and an ambulance outside the ornate 19th-century church.
Security footage from before the attack showed a pair of men wearing black ski masks with their hands hidden in their pockets. One was wearing sunglasses.
"Our security forces are conducting a large-scale investigation into the matter," he said.
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