A stampede at a food distribution site run by an Israeli-backed American organization in the Gaza Strip killed 20 Palestinians on Wednesday.

Israel’s air and ground war has destroyed vast areas of Gaza and driven some 90% of the population from their homes. Aid groups say they have struggled to bring in food and other assistance because of Israeli military restrictions and the breakdown of law and order, and experts have warned of famine.

Israel’s military said a “technical error” had caused munition to land dozens of meters from its target. The victims were gathered near a water distribution point, health workers said.