Two ships departed Sunday evening from the Greek island of Syros to join the Global Sumud Flotilla, an international mission that seeks to challenge and break the Israeli blockade of Gaza, AFP reported.

According to the report, roughly 500 people gathered at the port of Ermopoulis, chanting “Free Palestine” as the two Greek-flagged vessels, the Oxygen and Ilektra, set sail. The ships are carrying humanitarian goods for Gaza along with 13 crew members combined.

Kostas Fourikos, a 39-year-old crew member, stated the flotilla’s purpose is “to show Israel that it shouldn’t have the right to impose starvation” and “to send the message of solidarity to the Palestinians, who suffer so much.”

The two vessels are scheduled to join the rest of the fleet, which seeks to deliver aid to Gaza, where Israel’s military campaign against the terrorist group Hamas continues.

The Global Sumud Flotilla, which counts environmental activist Greta Thunberg among its supporters, claims to be an independent group not affiliated with any government or political party. The mission’s journey has been complicated by at least two alleged drone attacks while the ships were docked off the coast of Tunisia.

Tunisian authorities initially denied the presence of any drones in the area, but later reversed course and claimed that the vessels were targeted by a “premeditated attack”.

Thunberg was previously deported by Israel in June after taking part in another flotilla, the Madleen, which was intercepted by the IDF.

The activists were then given food and water, despite many of them having prepared prerecorded videos claiming that they were “kidnapped” by the IDF.

The Foreign Ministry said that the Gaza aid aboard the Madleen included less than a single truckload of aid, and it would be transferred to Gaza through real humanitarian channels.