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

Meanwhile, Israeli strikes killed 25 people across Gaza, according to local health officials.

Desperation is mounting in the Palestinian territory of more than 2 million, which experts say is at risk of famine because of Israel’s blockade and nearly two-year offensive. A breakdown of law and order has led to widespread looting and contributed to chaos and violence around aid deliveries, according to Associated Press.