Vacuum bombs, known as thermobaric weapons, harness the power of powdered metal to create a rapidly expanding fireball. Legally, their use is only allowed against military targets, and never against civilian targets.
As it reminds us Marc Garlasco , advisor to PAX, a Dutch-based peace organization, their use in populated areas would represent an open violation of international humanitarian law. From the fragmented information received, we are not sure that Russia is using them in the course of its 'special military operation' in Ukraine.
On February 28, the Ukrainian ambassador to the USA Oksana Markarova told reporters that the Russia is using thermobaric weapons: testimonies and images arriving from the web do not clarify the doubts, however. For the moment, the images show the presence on the field of a TOS-1 Buratino, a vehicle equipped with 24 rockets that can house thermobaric warheads.
In any case, the danger for the population is truly enormous, considering the destructive power of thermobaric devices.
TOS-1 launches indirect fire rockets with an area effect that has the potential to cause widespread death and destruction in towns and cities. Such weapons should never be used in areas with civilian concentration due to the likelihood of harm to civilians.
Marc Garlasco

How thermobaric weapons work
Normal explosives are activated by detonation, releasing more and more powerful energy. Thermobaric explosives, on the other hand, use metal powder that burns in the air. In a short time, the dust generates a fireball, which expands rapidly and creates a shock wave aimed outwards.
The shock wave generated by the pressure released by the bomb towards the outside is the reason why thermobaric weapons are considered highly dangerous.
People close to the blast can suffer from severe internal damage, often lung damage that receives excessive pressure. All this leads them to die without showing any visible wounds. That's not all: the damage generated by a thermobaric explosion can reach even the most protected areas. Bunkers, trenches and tunnels, all structures that usually protect against normal bombardment, have no power.
According to Garlasco, "The Russia has a history of using thermobarics against cities and towns in Syria. "This is why the councilor cannot explain the presence of TOS-1 in a city. Such a weapon remains absolutely illegal." It is difficult to understand how TOS- 1 can be legally used in a city. "