ISTANBUL (AP) – Cleaning workers on Saturday found an unexploded hand grenade on the roof at the seat of the spiritual leader of the world’s Orthodox Christians in Istanbul, four months after a grenade attack caused minor damage to the complex. Police said the grenade, found on the roof of the Cathedral of St George at the Phanar Ecumenical Patriarchate, posed no threat because of severe deterioration of its explosive capacity. [The Greek Foreign Ministry condemned the attack and said it had asked Turkish authorities to step up security at the Patriarchate.] The grenade was thought to have been thrown onto the roof during an October grenade attack, when another percussion grenade exploded and damaged parts of the roof as well as shattering windows there and in the main building of the Patriarchate complex. That attack came weeks after police clashed with hundreds of stone-throwing nationalist Turks who staged a protest outside the Patriarchate and burned an effigy of Patriarch Vartholomaios, whom far-right groups accuse of working against Turkish interests.