Istanbul conquest commemorated with Islamic prayers in Hagia Sophia
The prayers were held to celebrate the anniversary of the conquest of Constantinople, today's Istanbul, by the Ottomans in 1453.
"It is very important to commemorate the 567th anniversary of the conquest ... through prayers in the Hagia Sophia," said President Recep Tayyip Erdogan, who attended the ceremony via videoconference.
The stunning edifice was first built as a church in the sixth century under the Byzantine Empire as the centrepiece of its capital Constantinople.
After the Ottoman conquest, it was converted into a mosque before being turned into a museum during the rule of Mustafa Kemal Ataturk, the founder of modern Turkey, in the 1930s.
But there have been hints about reconverting the Hagia Sophia into a mosque. Last year, Erdogan himself mooted the possibility of turning Hagia Sofia museum into a mosque.
Such calls have sparked anger among Christians and raised tensions with neighboring Greece.
In 2015, a Muslim cleric recited the Koran in the Hagia Sophia for the first time in 85 years to mark the opening of an exhibition.
After Friday prayers at the Blue Mosque, a small group of Muslim worshippers shouted: "Let the chains break and let the Hagia Sophia open," an AFP photographer reported.
The group was later dispersed by the police who stopped them from protesting near Hagia Sophia that sits immediately opposite the Blue Mosque.
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