An American-made Patriot air-defense missile successfully intercepted one of the most sophisticated conventional weapons in Russia’s arsenal for the first time over Kyiv on Thursday night, the Ukrainian air force claimed on Saturday.
The downing of a Russian hypersonic Kinzhal missile by a Patriot missile, confirmed by three senior U.S. officials, appeared to offer the first proof that Russia’s hypersonic missiles — presented as invulnerable by President Vladimir V. Putin — could be defeated by current Western missile defense systems.
“I congratulate the Ukrainian people on a historic event,” Lt. Gen. Mykola Oleshchuk, the commander of the Ukrainian air force, said in a statement posted on the Telegram messaging app. “Yes, we have shot down the ‘unparalleled’ ‘Kinzhal.’”
The U.S. officials said that they had received information about the strike from the Ukrainian military through classified channels. One official added that U.S. military analysts were able to verify the claim using technical means. Nevertheless, independent analysts were reluctant to confirm the interception until more information was available about the type of missile Russia fired and whether it was hit by a Patriot.
The Patriot is by far the most expensive single weapon system that the United States has supplied to Ukraine, at a total cost of about $1.1 billion: $400 million for the system and $690 million for the missiles.
It was only last month that the first Patriot systems arrived in Ukraine, even though Kyiv had been pleading with the Pentagon for the weapons since the start of the war. For more than a year, Ukraine has had no air-defense system that could counter Russia’s arsenal of ballistic or hypersonic missiles like the Kinzhal.
Hypersonic missiles are long-range munitions capable of reaching speeds of at least Mach 5 — five times the speed of sound, or more than a mile a second. That speed was thought by many experts to render traditional air defense systems essentially useless, because by the time they can be detected on radars, they are already nearly at their target.
“It is invincible against all existing and prospective missile defense and counter-air defense systems,” Mr. Putin claimed in 2018. But Western analysts have remained skeptical, calling the missiles, modified versions of existing conventional munitions, “new wine in old bottles.”
Nevertheless, China and the United States are racing to develop and deploy hypersonic missiles, and numerous other countries are experimenting with the technology.
The powerful explosion that officials said was the destruction of the Kinzhal missile above central Kyiv rattled windows and jolted people out of bed. Fragments from the explosion littered the streets not far from the government quarter in the heart of the city and were collected by teams of forensic experts.
General Oleshchuk said the military waited to report the destruction of the hypersonic missile to protect operational security. He urged the public not to share information about air defenses as they work to counter Russian missiles and drones.
“We will definitely report what, where, with what, and when it was shot down,” he said. “All in its own time.”
The Patriot air defense system can fire three different types of missiles called interceptors, each designed to destroy different kinds of threats like warplanes, helicopters, cruise missiles, drones and even ballistic missiles. One, called PAC-3, can knock down enemy planes at a range of about 40 miles, and ballistic missiles at approximately 20 miles.
According to a classified document from the batch a Massachusetts airman is accused of leaking, the United States is sending the PAC-3 version to Ukraine. Germany and the Netherlands have teamed up to send a second PAC-3 version, the document indicated.
Under the right conditions, a Patriot might be capable of taking down one of the fast-moving Kinzhal missiles, according to Ian Williams, deputy director of the Missile Defense Project at the Center for Strategic and International Studies, a Washington think tank.
“Hitting a Russian Kinzhal with a Patriot missile would be tough but not impossible,” Mr. Williams said. “There are a lot of factors, such as where the Patriot is, where that Kinzhal was headed and whether or not it was maneuvering.”
While Kyiv and other cities across Ukraine have been bombarded with missiles, rockets, drones and bombs for more than a year, killing thousands of civilians, repeated attacks on Kyiv by Russian drones over the past two weeks have put many in the city on edge.
Ukraine has become adept at shooting down Russian cruise missiles and drones, often knocking 70 to 80 percent of them out of the sky in any particular attack. But those that penetrate the complex air defense network can do tremendous damage.
The Kinzhal, or Dagger, is a modified version of the Russian Army’s Iskander short-range ballistic missile, which is designed to be fired from truck-mounted launchers on the ground. Launching the missile from a warplane at high altitude, instead of from the ground, leaves it with more fuel to use to reach higher speeds.
Ukraine’s air force has said that Russia has used around 50 Kinzhals over the course of the war, including during the sustained assault on the Ukrainian energy grid in the fall and winter.
The Patriot system works most effectively as part of what the American military calls a “layered defense,” which includes systems used to down or thwart drones and warplanes, as well as a range of cruise and ballistic missiles, U.S. officials say. Previously, its general ability to counter weapons like Russia’s Kinzhal was unknown.
Following the U.S. pledge to provide the Patriot systems, Ukrainian soldiers were dispatched to Fort Sill, Okla., for a 10-week crash course in how to use them. They completed the training at the end of March and are now training others in Ukraine.
General Oleshchuk said that the use of Patriots as part of a layered air defense network should give the 3.6 million people living in Kyiv and people in other cities comfort.
“When loud explosions are heard in the air, my daughter reassures the neighbors every time with the words: calm down, our air defense system is working!” he said.
Here’s what else is happening in Ukraine:
Blast wounds a prominent Russian: A car bombing has injured a prominent Russian nationalist writer and killed his driver, Russian state media reported on Saturday. The state-run Tass news agency said that the writer, Zakhar Prilepin, was wounded but conscious. Preliminary information showed that an explosive device had been planted under Mr. Prilepin’s car in Nizhny Novgorod, Tass reported, but it did not say who was believed to be behind the attack.
More trouble at a nuclear plant: The United Nations’ nuclear watchdog agency said on Saturday that the situation at Europe’s largest nuclear power plant in southern Ukraine is “becoming increasingly unpredictable and potentially dangerous” as residents from the nearby town are being told to leave their homes and businesses by the Russian occupation authorities. The reactors at the Zaporizhzhia Nuclear Power Plant in the town of Enerhodar have been shut down, but thousands of workers are still needed to keep safety equipment running to prevent a meltdown. The evacuation of the town, where most of the workers live, has added to the risk of an accident, Rafael Mariano Grossi, the director general of the International Atomic Energy Agency, said in a statement. Mr. Grossi said he was alarmed by the “increasingly tense, stressful, and challenging conditions for personnel and their families.”
Russification efforts: Ukraine’s military said on Saturday that Russian officials are intensifying pressure on Ukrainian civilians in illegally annexed areas to obtain Russian passports, with occupation authorities in the town of Starobilsk going from home to home to enforce a new edict that allows for those who do not cooperate to be removed from their homes. The claim could not be independently verified. Russia has not allowed international journalists or organizations to access areas under its control. Ukrainian officials said investigators have been gathering evidence in recent days about efforts to force people to pledge allegiance to the Russian Federation by getting a passport, or else be considered foreigners without legal residency. Mr. Putin signed a decree on April 27 that says those who refuse can be deemed a threat and “deported,” according to the policy.
Prisoner swaps: Ukraine said on Saturday that 45 national guard members had been released from Russian captivity. Andriy Yermak, the top adviser to President Volodymyr Zelensky of Ukraine, said on Twitter that the 42 men and three women had defended the Azovstal steel plant in the port city of Mariupol, the scene of a brutal siege. Russia’s Defense Ministry said separately in a statement that three of its pilots had been released from Ukrainian captivity after “a difficult negotiation process.”
Marc Santora reported from Kyiv, Ukraine, and Eric Schmitt and John Ismay from Washington. Cassandra Vinograd contributed reporting from London, and Victoria Kim from Seoul.