Ukrainian President Volodymyr Zelenskyy on Thursday accused Russia of repeatedly using banned thermobaric weapons, also known as vacuum bombs, in cities across Ukraine.

"The forbidden vacuum bombs," Zelenskyy said in an interview for French TV translated by Interfax, were used "starting from Kharkiv and in other cities - there are already many such examples."

Russian Army TOS-1A "Solntsepyok (Blazing Sun)" multiple rocket launcher and thermobaric weapon mounted on a T-72 tank chassis

MOSCOW, RUSSIA - 2021/08/25: Russian Army TOS-1A "Solntsepyok (Blazing Sun)" multiple rocket launcher and thermobaric weapon mounted on a T-72 tank chassis seen during the annual Army Games defense technology international exhibition. s) (Getty)

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The banned weaponry is deployed in a series of charges that detonates dispersed fuel and oxygen in the air. The explosion creates a blast wave of extreme pressure and heat that builds a vacuum-like phenomenon when in an enclosed space – making it particularly effective in urban warfare.

The bomb can be launched by rocket or dropped from aircraft. When deployed the first charge disperses a fuel mixture that can penetrate any building opening.

The second charge then detonates the cloud and creates a vacuum that pulls in all surrounding oxygen – resulting in a massive fireball.

Russia was first accused of using the deadly weapon in February by Ukrainian Ambassador to the U.S. Oksana Markarova, the U.K. Ministry of Defense later confirmed the use of thermobaric warheads in a March 9 tweet

Firefighters climb a ladder while working to extinguish a blaze in a destroyed apartment building after a bombing in a residential area in Kyiv, Ukraine, Tuesday, March 15, 2022. Russia's offensive in Ukraine has edged closer to central Kyiv with a series of strikes hitting a residential neighborhood as the leaders of three European Union member countries planned a visit to Ukraine's embattled capital. 

Firefighters climb a ladder while working to extinguish a blaze in a destroyed apartment building after a bombing in a residential area in Kyiv, Ukraine, Tuesday, March 15, 2022. Russia's offensive in Ukraine has edged closer to central Kyiv with a series of strikes hitting a residential neighborhood as the leaders of three European Union member countries planned a visit to Ukraine's embattled capital.  (AP)


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The U.S. has yet to confirm its use in Ukrainian cities, though in a late February press conference White House press secretary Jen Psaki said if these accusations are found to be true "it would potentially be a war crime."

"There is nothing to prove, everything has already been proven there," Zelenskyy said Thursday.

Ukrainian authorities announced earlier this month that it was investigating reports that Russia may have used a chemical weapon in the partially besieged city of Mariupol.

"Different bombs are being used. We are checking the use of chemical weapons by the Russian Federation," the Ukrainian president said. "We act as fair people and are based on facts. Professionals, specialists should take samples, and when there is evidence, we will show what kind of chemical weapon and where they used it."

Ukrainian President Volodymyr Zelenskyy in Kyiv

Ukrainian President Volodymyr Zelenskyy speaks from Kyiv, Ukraine, on Tuesday. (Ukrainian Presidential Press Office via AP)

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Japan this week sent gas masks, hazmat suits and drones to Ukraine amid growing concerns that Russia will resort to chemical or biological warfare.

President Biden has said such a violation of the Geneva Convention will trigger a response, but it remains unclear how the U.S. or NATO would react.