Cluster munitions and vacuum weapons: What are the munitions that Russia is accused of using in Ukraine?

Russian forces, according to Ukraine and human rights groups, have also used cluster munitions in strikes on Kharkiv, the country’s second-largest city and a center of intense fighting between Ukrainian and Russian forces in recent days.

Shared videos on social media show Russian launchers for thermobaric weapons, often called “vacuum” weapons, rolling on the streets of Ukraine. A CNN team said it saw a Russian thermobaric missile system south of Belgorod, Russia, near the Ukrainian border on Saturday. And Oksana Markarova, Ukraine’s ambassador to the United States, accused Russia of using “vacuum bombs” in its invasion.

Ukraine’s second-largest city, Kharkiv, was heavily bombed on February 28th, killing at least 11 people and hospitalizing dozens. (Courtesy of Alexei Zavrazhniy)

White House spokeswoman Jen Psaki said she had seen messages used by Russia cluster and vacuum munitions against civilians in Ukraine, but could not confirm the accounts.

“If that were true, it would potentially be a war crime,” Psaki told a news conference Monday.

It remains unclear whether Russia’s use of weapons to date would constitute war crimes, as this will depend on the legal question of the extent to which Russian forces minimize the risk to civilians.

A senior U.S. defense official, speaking on condition of anonymity under basic rules set by the Biden administration, said Tuesday that Russia has launch systems in Ukraine “that could be used as a thermobaric weapon,” but U.S. officials cannot confirm the presence or use of such weapons in Ukraine.

The Kremlin has denied that the Russian military used cluster munitions or vacuum munitions during the invasion.

Here’s what you need to know about weapons, their legitimacy and the threat they pose to civilians.