At emotional DC memorial, Chef José Andrés mourns 7 World Central Kitchen aid workers killed by Israeli airstrikes

World Central Kitchen founder José Andrés delivered emotional and, at times, stirring remarks to an interfaith celebration of life held at the Washington National Cathedral on Thursday in honor of the seven aid workers with the chef's aid organization who were killed in a Gaza airstrike by Israel Defense Forces earlier this month.

Andrés mourned the members of his team, his voice pained with grief but resolute. He paid tribute to their dedication "to answer the call to serve on behalf of all humanity."

"[They] did everything to feed people they did not know and will never meet," Andrés said.

The service honored Palestinian Saifeddin Issam Ayad Abutaha; three British nationals, John Chapman, James Henderson and James Kirby; Jacob Flickinger, a dual U.S. and Canadian citizen; Lalzawmi "Zomi" Frankcom of Australia; and Damian Sobol of Poland.

Andrés shared detailed stories about each of the aid workers, including Chapman, who he said made others around him feel "loved and protected," and Flickinger, who he said "was a leader, a problem solver, a beacon."

Frankcom "was the living, breathing, smiling heart of everything we did … her compassion and curiosity were really infectious," said Andrés, who tearfully described her as a sister to him.

Israeli officials have repeatedly defended their military operations in Gaza, insisting they take steps to curb civilian deaths while allowing aid to flow in that cannot benefit Hamas.

An Israeli military investigation into how the strike that killed the workers occurred said that the decision to hit the aid convoy was a "serious violation" of their rules and noted that the team that carried it out lacked sufficient evidence to do so, twice violating operating rules. The IDF said they dismissed two officers, suspended two commanders and reprimanded three others as a result of the strike, which Israeli officials have described as a "grave" mistake.

Andrés said questions over the lethal strike on a marked aid truck, the conduct of the IDF, and the war itself must be met with moral clarity.

"I know we all have many unanswered questions about what happened and why. There is no excuse for these killings, none," Andrés said. "The official explanation is not good enough. And we still obviously demand an investigation into the actions of the IDF against our team. Even one innocent life taken -- is one too many."

The aid workers are among the roughly 200 humanitarian workers killed since Hamas' Oct. 7 terror attack on Israel sparked the war in Gaza, the United Nations has said.

The chef told mourners that the humanitarians with whom he worked consistently ran toward dire situations, injecting hope by cooking, distributing food and feeding souls.

"We stand next to communities as they feed themselves, nourish themselves, heal themselves," he said of his World Central Kitchen colleagues.

Andrés said standing next to those in need and facing their obstacles with them, together, made up the mission of the seven fallen people.

"People don't want our pity. They want our respect. Our only way to show respect is facing the mayhem alongside them. We remind them by showing up, that they are not alone in the darkness."

While the organization's work in Gaza has been suspended since the deadly strike, Andrés said that he hopes the World Central Kitchen continues its humanitarian work around the world, not just in Gaza, "carrying on the spirit of the fallen."

"We will not forget what they did for the hungry and for the world. We will honor their names. We will remember the life they lived," Andrés said.

President Joe Biden sent a private letter to Andrés expressing his condolences -- and Andrés then read it aloud to the families of the aid workers who died, a National Security Council spokesperson told ABC News in a statement. Second gentleman Doug Emhoff, who attended the memorial service, privately met with the families and offered his condolences, the spokesperson said.

ABC News' Fritz Farrow contributed to this report.