ATHENS — Organizers of a Gaza-bound flotilla carrying aid and pro-Palestinian activists said late Tuesday they heard explosions and saw multiple drones that targeted some of their boats, currently situated off Greece. "Multiple drones, unidentified objects dropped, communications jammed and explosions heard from a number of boats," the Global Sumud Flotilla said in a statement, without adding whether there were any casualties. "We are witnessing these psychological operations firsthand, right now, but we will not be intimidated," the statement said. Israel said Monday it would not allow the flotilla to reach Gaza. Israel blocked two earlier attempts by activists to reach Gaza by sea in June and July.