Mahir Polat, the head of Istanbul’s cultural heritage department, was recently released after being arrested along with other key cultural figures

Most of the Istanbul monument’s ancient frescoes and mosaics remain on view after restoration

Exhibition coincided with protests against the government's appointment of Melih Bulu as the new rector of Istanbul’s Bogazici University

Removal of ancient and modern specimens is latest run-in between President Erdogan’s government and foreign missions