More than 1,000 Palestinians have been killed by Israeli forces since May while trying to get food in Gaza, mostly near food sites run by an American contractor, the U.N. human rights office said.

More than 100 charity and human rights groups say that Israel’s blockade and ongoing military offensive are pushing Palestinians in the Gaza Strip toward starvation.

Gaza is facing a severe food crisis, with more than 100 humanitarian aid agencies warning that the population is on the brink of starvation.