Countries Speak Out After Greta Thunberg Was Detained by Israel Again "This is an illegal attack on unarmed humanitarians." ET Source: The Mega AgencyActivist Greta Thunberg is believed to be among the estimated 443 people being detained by Israeli troops. You can find out more about what the government is saying about the Israeli government's decision to detail Greta Thunberg below. @cnn Swedish climate activist Greta Thunberg has released a pre-recorded video calling for the release of her and the others who were captured. World leaders are speaking out about the detention of Greta Thunberg and other activists.