Swedish climate activist Greta Thunberg arrived in Greece on Monday to a cheering pro-Palestinian crowd after she and hundreds of other activists were deported from Israel following their attempt to deliver aid to Gaza by sea.

Israel said it expelled 171 activists, including Thunberg, bringing the total number deported so far to 341 out of 479 people detained when its forces intercepted the flotilla seeking to breach the naval blockade of Gaza.

Greek authorities said 161 activists, including 27 Greek nationals and citizens of nearly 20 other countries, arrived on a flight to Athens on Monday.

Let me be very clear. There is a genocide going on,” Thunberg told supporters at Athens airport.

Our international systems are betraying Palestinians. They are not even able to prevent the worst war crimes from happening,” she said, adding that the Global Sumud Flotilla was meant to act “when our governments failed to meet their legal obligations.”

The flotilla, consisting of dozens of vessels, set out to deliver humanitarian supplies and raise awareness about Gaza’s humanitarian crisis.

Most of Gaza’s 2.2 million residents have been displaced, and the UN says hunger there is widespread.

Israel, however, dismissed the mission as a “publicity stunt benefiting Hamas,” rejecting accusations of genocide and claims of severe hunger in Gaza.

It had previously detained Thunberg in June during a similar attempt to reach the enclave by sea.

Meanwhile, Swiss and Spanish participants of the flotilla alleged inhumane treatment during their detention, including sleep deprivation, lack of food and water, and physical abuse.

Israel’s foreign ministry denied the allegations, saying all detainees’ legal rights were respected. It said the only violence reported involved an activist who allegedly bit a female medic at Ketziot prison.

Nine Swiss activists returned home on Sunday, while Spanish activists also reported mistreatment after arriving in Spain following their deportation.