Organisers of a Gaza-bound flotilla carrying aid and pro-Palestinian activists said they heard more than a dozen explosions and saw multiple drones that targeted some of their boats.

"Multiple drones, unidentified objects dropped, communications jammed and explosions heard from a number of boats," the Global Sumud Flotilla said in a statement late Tuesday local time.

It did not add whether there were any casualties, where the boats are situated off Greece.

"We are witnessing these psychological operations firsthand, right now, but we will not be intimidated," the statement added.

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