The almost 20 months of war has torn Gaza apart, often displacing residents multiple times and killing more than 54,000 people, according to the Hamas-run Health Ministry. A U.S.-brokered ceasefire agreed in January collapsed in March as Israel enforced a blockade on all humanitarian aid into the strip.

Five days after climate activist Greta Thunberg set sail Sunday afternoon along with 11 other activists on a ship carrying aid to Gaza, the group could soon near Israeli waters. Israeli officials have vowed not to allow the ship,