But the news from home did not dampen the euphoric mood in Uman, about 200 km (125 miles) south of Kyiv, where the streets were filled with the sound of chants and rhythmic clapping.
"Everyone is good because we have God. That's it, there's nothing to worry about," said one of the visitors, who gave only his first name, Israel.
More than 30,000 ultra-Orthodox Jews arrived in Uman for Rosh Hashanah, according to the United Jewish Community of Ukraine. Another 14,000 were unable to reach the city, some of them because Iran's attack thwarted their travel plans.
Asked whether they had any concerns about the threat from Russia, which has been hitting Ukraine with missiles, drones and bombs as part of its full-scale invasion launched in 2022, pilgrim after pilgrim said they had none.
"Ukraine is safer than Israel. If you want a safe place, you come to Ukraine," said Akiva, who did not wish to give his surname, joking that the distance from Uman to the Russian border was greater than the entire length of Israel.
He said he had called relatives back home when he heard about the Iranian missiles.
"I called, but in the bomb shelter there was no reception. So after they got out of the bomb shelter, we called up. They were good, perfect," he said.
Several of the fervently religious visitors said they believed God was protecting the Jewish people, whether in Israel or in Ukraine.
"I feel bad (about the Iranian attack) but God has chosen us and saved us," said Avihai, who also did not give his surname.