A Gaza-bound flotilla of aid ships and pro-Palestinian activists reported explosions and multiple drone attacks near Greece, with communications on some vessels jammed, organizers said.

The Global Sumud Flotilla (GSF) confirmed the incidents, while activists, including German human rights worker Yasemin Acar and Brazilian activist Thiago Avila, said several boats were targeted.

Videos posted by the flotilla showed explosions and drones dropping devices on vessels, though no passengers or crew were harmed.

The 51-vessel flotilla, which includes Swedish climate activist Greta Thunberg, departed from Barcelona in late August to challenge the blockade of Gaza, The Guardian has reported.

Israel has reiterated that it will not allow the flotilla to reach Gaza, having blocked similar attempts in June and July.