Russia's use of vacuum bombs confirmed - but what are thermobaric rockets?

The Ministry of Defence (MoD) said its Russian counterpart had confirmed the use of thermobaric rockets creating “incendiary and blast effects” in the invasion.

A video posted to Twitter by the MoD said the weapons were used by Russia in both Afghanistan and Chechnya.

It comes as the MoD said the Russian state “almost certainly maintains extensive links” with Russian private military companies (PMCs) and is “likely deploying” their mercenaries to Ukraine.

“Russian PMCs have been accused of committing human rights abuses in several countries, such as Syria, Libya and the Central African Republic, whilst operating on behalf of the Russian state,” the MoD said.

Russian President Vladimir Putin (Alexei Nikolsky/AP)

What are vacuum bombs and is it illegal to use them?

Better known as a vacuum bomb, thermobaric weapons or warheads use oxygen in the air to create a high-temperature explosion - emitting a deadly shock wave in the surrounding area.

Thermobaric weapons are not illegal but their use is strictly regulated, the MoD said.

Vacuum bombs can cause slow and painful deaths as the shock wave sucks oxygen from the lungs of anyone in the vicinity.

The blast wave is generally significantly longer in duration than that of a conventional explosive with the capability to vaporise human bodies in moments.

The US Central Intelligence Agency (CIA) has a study that states vacuum bombs can “obliterate” anybody “near the ignition point”, according to the Independent.

The CIA study reads: “Those at the fringe are likely to suffer many internal, thus invisible injuries, including burst eardrums and crushed inner ear organs, severe concussions, ruptured lungs and internal organs, and possibly blindness.”

Another Defense Intelligence Agency document suggests that those hit by the pressure waves could “suffer for several seconds or minutes while they suffocate”.