Under Ottoman rule the church was ceded to Defterdar Ahmet Pasha, who converted it into a mosque bearing his name. The bell tower was demolished and replaced by a minaret. In an act of desecration, the conquerors destroyed the frescoes and Christian tombs.
The church in Ottoman times
biographies

The Venetian Basilica of St. Mark in the early 20th century, with a clock tower and minaret, 1900 - 1905 (G. Gerola, Monumenti Veneti, Heraklion)
The south side of the church and the Turkish minaret, 1900 - 1905 (G. Gerola, Heraklion)