KYIV, Ukraine — A Russian missile slammed into a hotel before dawn Thursday in the hometown of President Volodymyr Zelenskyy in central Ukraine, killing at least four people and injuring more than 30 others, Ukrainian authorities said.

“Just before the attack, volunteers from a humanitarian organization — citizens of Ukraine, the United States and the United Kingdom — had checked into the hotel,” Zelenskyy said in a statement. “They survived because they managed to get down from their rooms in time. Unfortunately, four people were killed in this attack.”

“There must be no pause in the pressure on Russia to stop this war and terror against life,” he said.

As rescue workers raced to pull wounded civilians from the ruined building in Zelenskyy’s hometown, Kryvyi Rih, air-defense crews across the country scrambled to defend against bombardments that have become routine during the winter.

In total, the Ukrainian air force reported, Russia launched two ballistic missiles and 112 drones — including some with dummy warheads designed to expose and exhaust air defenses.

Most of the deadly drones were shot down, the air force reported, but it did not say whether either of the missiles had been downed.

After the United States announced this week that it was suspending both military and intelligence assistance to Ukraine, there has been growing concern that the nation’s air-defense capabilities would be among the first elements of its defense to be compromised.

The American-made Patriot system has proved to be Ukraine’s most reliable defense against Russia’s most sophisticated ballistic missiles. The pause in U.S. military assistance could leave Ukrainians short of the sophisticated interceptor missiles that have helped provide a blanket of protection over the capital, Kyiv, and other cities.

At the same time, Ukraine’s air-raid alerts are informed, to some degree, by the early warning data provided by American satellites, which can detect aircraft and missile launches deep in Russian territory. It is not clear if the pause on intelligence sharing included information related to those systems. Ukrainian authorities sought to reassure the public that they were taking steps to address the fallout from the sudden moves by its primary military ally as Washington increasingly aligns itself with Moscow as it applies pressure to Ukraine before peace negotiations.

Even as Ukraine works to persuade Washington that it should be applying pressure to Russia to bring the war to an end rather than taking steps that weaken Ukraine’s ability to defend itself, Ukraine is also appealing directly to the American public.

Ukrainian operators of Patriot systems have followed the lead of F-16 fighter pilots in calling directly on the American people to stand with Ukraine.

“Thanks to your support, we are still alive, and we are able to protect our cities and the civilians who live there,” said one operator in a video released by the military. “Thank you to the American people!”