Israeli forces conducted at least eight strikes on aid workers' convoys and sites in Gaza since October, despite these organisations giving Israeli authorities their coordinates, Human Rights Watch (HRW) has said.
Israel did not give advance warnings to any of the aid groups prior to the attacks, which killed or injured at least 31 people, the rights organisation said in a press release on Tuesday.
In one well-known incident on 1 April, Israeli strikes killed seven aid workers with food relief group World Central Kitchen (WCK), leading to widespread international uproar.
"Israel's killing of seven World Central Kitchen aid workers was shocking and should never have happened under international law," said HRW associate crisis, conflict, and arms director Belkis Wille.
"Israel's allies need to recognise that these attacks that have killed aid workers have happened over and over again, and they need to stop."
These strikes were not an isolated "mistake" but one of at least eight instances where aid groups had given Israel their convoy or premises' coordinates but were subsequently attacked without warning, HRW said.
Other incidents include attacks on a Doctors Without Borders (MSF) convoy on 18 November, an International Rescue Committee (IRC) and Medical Aid for Palestinians (MAP) guest house on 18 January, and a convoy belonging to UN's Palestinian refugee agency, UNRWA, on 5 February.
The eight attacks show "fundamental flaws" with the so-called deconfliction system, HRW said, which was established to allow aid workers to safely deliver critical assistance in the Gaza Strip, whose inhabitants are threatened by a famine resulting from Israel's war and siege.
At least 254 aid workers were killed in Gaza between 7 October and 30 April, among them 185 United Nations staff, the UN humanitarian office, OCHA, said.
HRW recently met staff from 11 humanitarian groups and UN aid agencies working in Gaza who said Israeli attacks on aid workers had made them take various measures included periodically halting work, cutting the number of staff in Gaza, or seriously limiting their aid operations in other ways.
"I can't risk sending more staff into Gaza because I cannot rely on deconfliction as a way of keeping them say," a senior employee from a group whose guest house was attacked told HRW, which they said was a central factor in restricting the organisation's ability to provide medical services.
"You can build docks and send shipments, but without a safe operating environment, you will have a pile up of shipments that people aren't able to deploy safely to help people."
HRW said the pattern of attacks, despite prior notifications, poses serious questions about Israel's commitment to comply with international humanitarian law and the laws of war.
Israel's war on Gaza has so far killed at least 35,173 people, according to the Palestinian enclave's health ministry, and injured 79,000 more.
Ambulances, hospitals, and residential buildings have come under attack in the seven-month Israeli military offensive, which has devastated Gaza's infrastructure.
