KRYVYI RIH, Ukraine — A salvo of cruise missiles slammed into the industrial Ukrainian city of Kryvyi Rih on Wednesday, damaging a dam and sending water gushing downstream.
Videos on social media showed pedestrian bridges being washed away and foamy white water rising along the river banks in the city, in southern Ukraine, where Kyiv’s forces are carrying out a counteroffensive. Residents said that a large dam was hit on the Inhulets River, a strategic waterway, and many were worried about flooding.
As the water level of the river rose on Wednesday night, local officials urged people who live nearby to evacuate. Residents would be taken by bus to shelter at local schools, said Oleksandr Vilkul, the military governor of Kryvyi Rih.
“If the water has not reached you, it will come soon,” Mr. Vilkul wrote on his Facebook page.
About 100 cubic meters of water was leaking from the dam every second, according to Kyrylo Tymoshenko, a senior official in the office of President Volodymyr Zelensky. “This is a significant volume,” he said in a post on the messaging service Telegram. “And the water level in the Inhulets River changes every hour.”
Mr. Zelensky condemned the attack in his nightly address.
Russia was hitting “objects that have no military value at all,’’ he said, speaking in Russian. “You are weaklings waging a war against civilians.”
Ukrainian officials have accused Russia of targeting civilian infrastructure in response to recent battlefield losses in the northeast, where a fast-moving offensive reclaimed a swath of territory outside the country’s second largest city, Kharkiv. Earlier this week, Russian forces knocked out electricity to much of the city, though it has been restored.
Military analysts suggested the Russians may have targeted the dam to make the river level rise and frustrate Ukraine’s counteroffensive in the south. The Inhulets separates the bulk of Ukraine’s forces from their Russian counterparts.
The missile strike occurred around 5 p.m., shattering the quiet of what had been a placid afternoon in Kryvyi Rih, Mr. Zelensky’s hometown.
At one school, volunteers sewed fabric camouflage coverings, for soldiers to cover their checkpoints or equipment. Several participants said they have felt more motivated after a string of Ukrainian military victories over the past week liberated thousands of square miles of occupied territory.
“I know it will take more time,” said Oksana Savosko, who used to work in a grocery store and now volunteers to help the war effort. “But I can already feel the mood of victory.”
Oleksandr Chubko, Oleksandra Mykolyshyn and Vivek Shankar contributed reporting.
