An unusual call to prayer sounded across Istanbul on Friday night (July 15), during a failed military coup against the Turkish government.

The calls, called azan, are usually sung for funerals or for Friday prayers.

But the calls last night came unusually late, and kept going. They were being used to call citizens into the streets after Turkish president Recep Tayyip Erdogan asked citizens to protest the attempted overthrow.

“I urge the Turkish people to convene at public squares and airports. I never believed in a power higher than the power of the people,” he said in a statement strung together using Apple’s FaceTime app and broadcast on Al Jazeera.

Erdogan returned to Istanbul several hours later to huge crowds at the airport, in a strong signal that the military’s control was slipping. By morning, it was apparent that the coup had failed.

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