Live updates: Russia’s war in Ukraine

In this 2018 photo, a Russian Air Force MiG-31K jet carries a Kh-47M2 Kinzhal missile during a Victory Day military parade in Moscow. (Alexander Zemlianichenko/AP)Russia has used about 10 to 12 hypersonic weapons during the war in Ukraine, a senior US defense official said Tuesday.  Cautioning that the US does not have a “perfect count,” the official said the number of hypersonic weapons Russia has used is “probably between 10 and 12 I think would be about right.”Though the official did not specify the dates and locations of the launches, US officials observed the first known combat use of the Russian air-launched Kinzhal hypersonic missile against a building in western Ukraine.The official would not corroborate Ukraine’s claim that Russia had fired Kinzhal missiles at Odesa over the weekend. Sergey Bratchuk, a spokesperson for the Odesa regional military administration, said Russia had fired three Kinzhal missiles at a “tourist infrastructure target.”The US has seen no indications that Russia used hypersonic weapons in these strikes, the US official said. “Obviously, we’ve seen them use hypersonics in the past and hitting buildings, but I don’t have anything to indicate that they were used in Odesa,” said the official.The Kinzhal missile, which became operational in 2017, has a claimed top speed of Mach 12, or about 9,000 miles per hour (more than 14,400 kilometers per hour). It is an air-launched version of the Russian Iskander short-range ballistic missile.US officials downplayed the significance of the Russian use of their hypersonic Kinzhal missile. US Defense Secretary Lloyd Austin said he did not view it as “some sort of game changer” after the Russians announced the missile launch. Days later, Pentagon press secretary John Kirby said it was “hard to know what exactly the justification” was for the launch, since it targeted a stationary storage facility.”That’s a pretty significant sledgehammer to take out a target like that,” Kirby said at the time. Russia also claimed it used Iskander missiles in April to strike weapons depots and Ukrainian military equipment.Ukraine, on the other hand, claims Russia used Iskander missiles launched from Crimea to strike at a settlement in the Odesa district in early April.More on hypersonic missiles: Essentially, all missiles are hypersonic — which means they travel at least five times the speed of sound. Almost any warhead released from a rocket miles in the atmosphere will reach this speed heading to its target. It is not a new technology.What military powers — including Russia, China, the United States and North Korea — are working on now is a hypersonic glide vehicle (HGV). An HGV is a highly maneuverable payload that can theoretically fly at hypersonic speed while adjusting course and altitude to fly under radar detection and around missile defenses.An HGV is the weapon that’s almost impossible to stop. And Russia is thought to have an HGV in its arsenal, the Avangard system, which Russian President Vladimir Putin in 2018 called “practically invulnerable” to Western air defenses.CNN’s Brad Lendon contributed reporting to this post.