World Central Kitchen, the biggest provider of food aid in the Gaza Strip after the United Nations, said Tuesday that it was pausing operations across the Middle East after seven of its workers including a U.S.-Canadian dual citizen were killed in what it said was an Israeli airstrike.

The group said its workers had coordinated their movements ahead of time with the Israeli military. Rear Adm. Daniel Hagari, the Israeli military’s chief spokesman, expressed “sincere sorrow” and said it was reviewing the circumstances of the incident.

The pause threatens to exacerbate the humanitarian crisis in the Palestinian territory, with more aid groups expected to suspend their activities out of fear for their staff’s safety. More than one million people are estimated to be starving in Gaza as a result of the war Israel launched against Hamas in response to the Oct. 7 attacks, which Israeli authorities say killed 1,200 people, mostly civilians.

The aid workers’ deaths drew condemnation from Western capitals and risk further isolating Israel over its conduct in the war, which has killed about 33,000 Palestinians in Gaza, mostly women and children, according to health authorities in the territory. The numbers don’t distinguish between militants and civilians.

U.N. World Food Program Director Cindy McCain said she was shocked and heartbroken by the World Central Kitchen deaths. “This attack on our humanitarian community is unacceptable,” she tweeted. “The safety of aid workers is paramount, as is the safety of those who come to receive aid.”

Palestinians carry the body of a foreign employee from the World Central Kitchen (WCK), who was killed with other fellow workers in an Israeli airstrike, according to the NGO as the Israeli military said it was conducting a thorough review at the highest levels to understand the circumstances of this “tragic” incident, amid the ongoing conflict between Israel and Hamas, at a hospital in Deir Al-Balah, in the central Gaza, Strip April 2, 2024. REUTERS/Ramadan Abed

World Central Kitchen, which was founded by celebrity chef José Andrés, runs field kitchens that provide free hot meals during crises, such as earthquakes and floods. It first operated in a war zone in Ukraine.

In Gaza, the Washington-based group has ramped up operations since Oct. 7 to provide 300,000 meals a day, making deliveries by truck, airdrop and by sea through  a maritime corridor that it pioneered  with an initial shipment last month. President Biden said last month that the U.S. military would build a pier off the coast of Gaza to enable aid deliveries by sea, but the pier hasn’t been put in place yet.

In a war that poses unprecedented challenges for humanitarian organizations used to operating in the world’s toughest environments, World Central Kitchen has punched above its weight in Gaza. While the U.N. provides nearly 80% of humanitarian aid, World Central Kitchen accounts for more than half of non-U.N. deliveries, mostly food, according to Cogat, the Israeli military body coordinating aid there.

Badges on a jacket read “World Central Kitchen” after, according to the Hamas-run Gaza government media office, WCK employees, including foreigners, were killed in an Israeli airstrike on Gaza, while the Israeli military, commenting on the reports, said it was conducting a thorough review at the highest levels to understand the circumstances of what it called a tragic incident, in Deir al-Balah, Gaza April 1, 2024 Video Obtained by Reuters/Handout via REUTERS THIS IMAGE HAS BEEN SUPPLIED BY A THIRD PARTY. NO RESALES. NO ARCHIVES

A second convoy of ships organized by World Central Kitchen that departed from Cyprus over the weekend arrived late Monday and began to unload some 400 tons of food. World Central Kitchen said its workers, who were traveling in two armored cars branded with the group’s logo and a soft-skin vehicle, were hit as they left a warehouse in the central Gaza city of Deir al-Balah where they had deposited food from the ships.

A spokeswoman for World Central Kitchen said the ships were sent back to Cyprus after the incident, having only unloaded a quarter of the food they were meant to deliver.

World Central Kitchen blamed the deaths on a targeted attack by the Israeli military.

“This is not only an attack against WCK, this is an attack on humanitarian organizations showing up in the most dire of situations where food is being used as a weapon of war,” said Chief Executive Erin Gore. “This is unforgivable.”

The victims included three British nationals, a U.S.-Canadian dual-citizen, one Palestinian, an Australian and a Polish citizen, according to World Central Kitchen.

Humanitarian aid falls through the sky towards the Gaza Strip after being dropped from an aircraft, amid the ongoing conflict between Israel and the Palestinian Islamist group Hamas, as seen from Israel, April 1, 2024. REUTERS/Hannah McKay

White House national security spokeswoman Adrienne Watson tweeted that the U.S. was “deeply troubled” by the strike and called on Israel to investigate.

Poland’s Foreign Ministry condemned the death of Polish aid worker Damian Sobol. “Poland does not agree with the absence of compliance to international, humanitarian law and the protection of civilians, among them humanitarian workers,” it said on X. Deputy Justice Minister Arkadiusz Myrcha called for an investigation on state television.

The Australian aid worker was identified as Zomi Frankcom.

Australian Prime Minister Anthony Albanese called the strike “completely unacceptable.” He said he expected full accountability for the aid workers’ deaths and that the Foreign Ministry had requested a call with the Israeli ambassador to Canberra.

“This is beyond any reasonable circumstances—that someone going about providing aid and humanitarian assistance should lose their life,” he told reporters.

Write to Stephen Kalin at