The activists had set out to protest Israel’s ongoing military campaign in the Gaza Strip, which is among the deadliest and most destructive since World War II, and its restrictions on the entry of aid.

Swedish campaigner Greta Thunberg was deported from Israel, the Israeli Foreign Ministry said, the day after the Israeli navy prevented her from sailing to Gaza.

Israel said it deported Greta Thunberg one day after its navy intercepted a Gaza-bound flotilla carrying aid. Thunberg was one of 12 passengers on board.

Israel is supporting armed groups of Palestinians in Gaza in what it says is a move to counter Hamas. But officials from the U.N. and aid organizations say the military is allowing them to loot food and other supplies from their trucks.

Prime Minister Benjamin Netanyahu acknowledged only that Israel had been working with “clans.” But the opposition leader warned that the “weapons going into Gaza will eventually be pointed at Israeli soldiers and civilians.

It is almost 20 months since Israel launched a military campaign in Gaza in response to the Hamas-led cross-border attack, in which about 1,200 people were killed and 251 others were taken hostage. At least 54,677 people have been killed in Gaza during the war, according to the territory's health ministry.