Professors, researchers, and graduates of the Weizmann Institute of Science in Rehovot are “in mourning” over the massive physical devastation some of its buildings suffered after ballistic missiles from the Islamic Republic of Iran blasted the campus last week.

They were grieving not only over the destroyed labs, equipment, tissue samples, lab animals, and the work of Israeli and foreign students that had been disrupted, but also over the setback in scientific research that was aimed at benefiting humanity, reducing suffering, and saving lives.

The institute has some 2,500 researchers and staff in over 30 labs that train graduate students in mathematics, physics, chemistry, biology, biochemistry, and computer science.

The scope of the damage  

The Ullmann Building of Life Sciences, where researchers are dedicated to cancer research, and the Institute for Environmental Sustainability were the hardest hit, and it’s likely that they will have to be demolished and rebuilt. The estimate of a leading academic on campus was that constructing a basic, unfurnished lab building would cost $50 million, and the cost of advanced scientific equipment would be up to five times that amount.
A building at the campus of the Weizmann Institute of Science remains damaged following an Iranian missile strike on Sunday, in Rehovot, Israel June 19, 2025 (credit: REUTERS/VIOLETA SANTOS MOURA)
A building at the campus of the Weizmann Institute of Science remains damaged following an Iranian missile strike on Sunday, in Rehovot, Israel June 19, 2025 (credit: REUTERS/VIOLETA SANTOS MOURA)
While several buildings on the Weizmann’s Rehovot campus were damaged, and a number of laboratories were destroyed by unintercepted missiles coming from Iran earlier this week, thankfully, no one was hurt. Nevertheless, the loss was devastating for cancer researchers and others whose laboratories were housed in the Ullmann Building.

Senior cancer researcher Dr. Leeat Yankielowicz-Keren told The Jerusalem Post that she was in mourning over the loss of irreplaceable cancer samples in her tumor immunology laboratory. She noted that all the written data that she and her team of 12 scientists had compiled about the tumor samples were still safely stored.

"Destroyed scientific devices, despite costing hundreds of thousands of shekels, could be replaced, but the samples themselves were one of a kind," she said. 

The lost scientific research lying among the rubble

The loss of “the many tumor samples collected over five years from cancer patients, not only in Israel but also in the United States, France, Switzerland, and other countries,” was devastating, she added. On a positive note, the senior cancer researcher noted that from the destruction, Weizmann was “already rebuilding. Institute heads are working around the clock; they have been wonderful. We are starting to build again, temporarily in other spaces on campus or sharing labs.”

When Prof. Eldad Tzahor’s cellular and molecular biology laboratory of regenerative medicine was totally destroyed, the world leader in cardiac regeneration, posted on social media: “This is hard and sad, as nothing was left to save. We study regenerative medicine – so we will regenerate, regrow, and rebuild. One of my students said, the one thing that wasn’t gone is our motivation.” Tzahor and his scientific team aim to develop preventive treatments for healthy young hearts that would allow them to remain strong.

At her campus laboratory – her “second home” – Prof. Ruth Arnon, Weizmann’s Paul Ehrlich professor of immunology, has been researching, among other things, anti-cancer vaccinations. The buildings could be reconstructed, Arnon told the Post, but “everything inside was lost.”

“Valuable tissue samples” had been destroyed, she explained, and research disrupted, causing a “setback in scientific research that was aimed at benefiting mankind – saving lives and reducing suffering.” Now, she said, “I don’t know if our lab animals are alive. I regard the damage as a personal tragedy.”

Reactions from staff and professors at Weizmann

World-renowned computer scientist Prof. David Harel – president of the Israel Academy of the Sciences and the Humanities since 2021 – has been at the Weizmann Institute since 1980. He said that “the lab suffered broken glass and fallen ceiling panels from the force of the blast, but we hope that we can resume working there in two weeks."

Harel has worked on computability theory, logics of programs, database theory, automata theory, software and systems engineering, visual languages, graph layout, modeling biological systems, odor synthesis and communication, and prosody analysis. He received the Israel Prize for his prodigious efforts.

He also studies prosody – the rhythm, stress, intonation, and other vocal characteristics of speech that go beyond individual sounds to convey meaning, and how they contribute to the overall interpretation of spoken language, including aspects like emphasis, emotion, and grammatical structure. 

“The side of the building is only about 40 meters from the Ullman Building that suffered so much devastation,” he said.

Harel commended the institute’s management, headed by president Prof. Alon Chen, for “an incredible job since the attack. I take my hat off to them.”

After the attack, Chen reported that “the missiles completely erased decades of research; we will need to start from scratch.” It’s likely that the three buildings will have to be demolished and rebuilt at an astronomical cost.

Harel said that “many individual colleagues from abroad – including those from the Max Planck Society for the Advancement of Science in Germany and even the country’s science minister – have contacted me to express sympathy and ask how they can help,” he said. “But journalists in Holland, for example, attacked us for allegedly being connected to the war, even though we are an academic, not a military, institution.” 

The best and brightest

Immunology

Prof. Ruth Arnon at Weizmann’s Paul Ehrlich Professor of Immunology, researches anti-cancer and influenza vaccinations. She began studying at the Rehovot campus after completing her master’s and PhD degrees at the Hebrew University of Jerusalem and working as a research assistant to Prof. Ephraim Katzir (who became Israel’s fourth president) and Prof. Michael Sela, with whom she developed the multiple sclerosis treatment drug Copaxone. She served as vice president of the Weizmann Institute and president of the Israel Academy of the Sciences and Humanities. 

Computer science 

Prof. David Harel, who has served as president of the Israel Academy of the Sciences and the Humanities since 2021, is a renowned computer scientist who has been at the Weizmann Institute since 1980.

Born in London, he was dean of the Faculty of Mathematics and Computer Science at the institute for seven years. He has worked on computability theory, logics of programs, database theory, automata theory, software and systems engineering, visual languages, graph layout, modeling biological systems, odor synthesis and communication, and prosody analysis. He received the Israel Prize for his prodigious efforts.

His research interests have focused on several areas of theoretical computer science, such as computability, logics of programs, and database theory. He is currently working on software and systems engineering; visual languages and their underlying methodologies and tools; the modeling and analysis of biological systems; and the synthesis and communication of smell. He also studies prosody – the rhythm, stress, intonation, and other vocal characteristics of speech that go beyond individual sounds to convey meaning, and how they contribute to the overall interpretation of spoken language, including aspects like emphasis, emotion, and grammatical structure.