The UK has demanded a “full” explanation from Israel over the killing of three British citizens in a drone strike targeting an aid convoy in Gaza.

Benjamin Netanyahu, Israel’s prime minister, admitted on Tuesday that the IDF was behind the strike on the World Central Kitchen convoy, which killed seven aid workers.

The charity had alerted the IDF to the route it was using and was travelling in cars marked with its logo on the roof.

Mr Netanyahu said the strike was “unintended” and described it as a tragic event of the kind that “happens” in wartime.

Rishi Sunak said he was “shocked and saddened” by the deaths and called on Israel to “provide a full and transparent explanation”.

Lord Cameron, the Foreign Secretary, described the killing of three British citizens as “completely unacceptable” in a phone call with his Israeli counterpart Israel Katz.

Israel must make “major changes to ensure the safety of aid workers on the ground,” Lord Cameron said.

The Foreign Office summoned the Israeli ambassador to the UK, Tzipi Hotovely, for a meeting over the strike. Lord Cameron has cut short his Easter break to handle the crisis.

The strike on the convoy was carried out by drone, The Telegraph understands, via an operator with the 933 brigade based in the southern city of Khan Younis.

It would have been signed off by three people - an intelligence officer, a unit commander and a legal adviser.

An Israeli military source branded the strikes an ‘intelligence failure’, saying that suspicions of the convoy were based on intelligence and heightened by it travelling at night.

A full explanation would likely be available within 24 hours, the source said, as the decision-making process would have been documented.

Israeli security officials told Haaretz newspaper that the convoy was trailed by IDF drones and fired upon three times.

The IDF believed an armed Hamas operative had joined a WCK convoy transporting 100 tonnes of food aid to its warehouse in the central city of Deir Al-Balah. The food had been delivered by sea from Cyprus.

Subsequent intelligence revealed that when the convoy left the warehouse, the Hamas operative stayed behind, the sources told Haaretz.

An Israeli drone reportedly fired a missile at one of the cars in the convoy, after which the aid workers moved to another vehicle, informing their superiors they had been attacked.

A second missile then hit the car they had moved to, according to Haaretz. When the third car in the convoy approached and tried to move the wounded, a third missile struck, killing everyone, the newspaper reported.

Bellingcat, an open-source intelligence website, reported that the destroyed cars were found around 1.6km apart, corroborating the report of three separate strikes.

The cars appeared to have been hit with inert or low-yield missiles, similar to the “Hellfire R9X” used by the US military, Bellingcat reported. The Hellfire contains no explosives and kills targets through sheer kinetic force.

In Haaretz, a defence source expressed his frustration with troops in the field who “launch attacks without any preparation, in cases that have nothing to do with protecting our forces.”

Photographs from the attack site showed a hole in the roof of one of the convoy’s cars, right through the middle of the WCK logo. The car was otherwise largely undamaged, suggesting explosives were not used in the strike.

The IDF said on Tuesday it had launched a high-level investigation into the incident while Mr Netanyahu described it as a “tragic case of our forces unintentionally hitting innocent people in the Gaza Strip.

“This happens in war, and we will investigate it to the end. We are in contact with the governments involved, and we will do everything to ensure that this does not happen again,” he said.

The IDF’s spokesman expressed “sincere sorrow” to the families of the victims, promising “an in-depth examination at the highest levels to understand the circumstances of this tragic incident.”

“We have been reviewing the incident at the highest levels to understand the circumstances of what happened and how it happened,” Rear Admiral Daniel Hagari said, lauding World Central Kitchen’s “vital mission of bringing food to people in need”.

“We will be opening a probe to examine this serious incident further. We will get to the bottom of this and we will share our findings transparently.”

The killed workers included Australian, Canadian and Polish citizens as well as a US-Canadian dual national.

World Central Kitchen described the attack as “unforgivable”.

“This is not only an attack against WCK, this is an attack on humanitarian organisations showing up in the most dire of situations where food is being used as a weapon of war,” said Erin Gore, the charity’s chief executive.

The organisation said it was suspending its operations in the region in the aftermath of the attack.

Cyprus said that ships bringing 240 tonnes of aid to Gaza would return to port now that the NGO was no longer working in the field.

The deadly attack was particularly shocking to the aid world since Israel held a broadly positive relationship with WCK, unlike other groups working in Gaza such as UNRWA, the UN’s agency for Palestinian refugees.

In his statement, Adm Hagari praised WCK for delivering aid to Israel in the aftermath of the October 7 massacre.

“WCK is thought to have the closest cooperation with the IDF and seemed to enjoy preferential treatment for being from its perspective ‘neutral’ (i.e. no advocacy work). In the end, the truth remains that no one is safe in Gaza,” Tania Hary, director of the prominent Israeli human rights organisation Gisha, said on Tuesday.

Juliette Touma, a UNRWA spokeswoman, called the Israeli attack on the aid workers “absolutely devastating.”

“It shouldn’t happen, but what’s been happening way too often in this conflict is that all the red lines have been crossed. Too many aid workers have been killed. Too many medical workers, too many journalists, too many children,” Ms Touma told the Telegraph.

At UNRWA alone, 176 workers have been killed by Israeli strikes in Gaza since the start of the war, including most recently in a “precisely targeted” Israeli bomb on an aid warehouse in Rafah in southern Gaza. Israel claims to have killed a Hamas commander Muhammad Abu Hasna in the attack.

NGOs on the ground are expressing their grave concern that de-conflicting with the IDF is “not functioning properly”, Tess Ingram, a spokesman for Unicef, told the Telegraph by phone from Gaza.

“Those of us working here understand that this is a very dangerous place… [but] we lost seven colleagues last night because that system didn’t work properly,” she said.

Australian authorities on Tuesday confirmed the death of Lalzawmi “Zomi” Frankcom, a 44-year-old woman from Melbourne.

On Tuesday, Nate Mook, a former colleague, spoke of her as embodying “the greatest aspects of humanity” in a post on X. 

Ms Frankcom was seen in a video last week filmed inside a field kitchen in Deir l Balah, where chefs were making rice with beef and vegetables.

Another victim has been identified as Damian Sobol, a Polish national from a city on the Ukrainian border who took up charity work following the Russian invasion of Ukraine in 2022.