JAPAN's "Unit 731" committed some of the most notorious war crimes the world has ever seen.
A notorious branch of the imperial Japanese army, it carried out horrifying human experiments and murdered more than 200,000 people during World War Two.
The inhumane sect conducted their gruesome tests and experiments on Chinese, Korean, Russian and American captives - and not just the men, either.
Women and children also fell victim to the brutal torture methods before they were eventually killed by Unit 731's ghastly acts.
Injected, shot at, dismembered and raped, the captives endured a hellish end to their lives.
Brighton beach evacuated as bomb squad blow up 'World War 2 shell' near pier
One of Unit 731's horrific acts was frostbite testing, where captives’ limbs were submerged in a tub of water filled with ice.
Their arms and legs would be held until they had frozen solid and a coat of ice had formed over the skin.
But it didn't end there, as sick members of the Japanese unit then tried different methods for rapid rewarming of the frozen appendage.
This would be done by dousing the limb with hot water, holding it close to an open fire, or just simply leaving the subject untreated overnight to see how long it took for their blood to thaw out.
Frostbite testing was just one of many horrendous torture techniques used by Japan's Unit 731.
Another involved breeding the most lethal strains of germs to wipe out the Chinese population.
Doctors monitored patients for rapid onset of symptoms and quick progression - and shot those who recovered.
Those who got sickest fastest were bled to death on a mortuary table, and their blood was used to transfect other captives.
The sickest would then be bled to transfer the most virulent strain to yet another generation.
When most of the blood had been siphoned off and the heart was too weak to pump anymore, an officer in leather boots would climb onto the table and jump on the victim’s chest with enough force to crush the ribcage.
Vital to celebrate Windrush pioneers, says Lenny Henry ahead of 75th anniversary
Other chilling experiments consisted exposing human subjects to dehydration, killing them inside spinning centrifuges, injecting them with diseased animal blood and zapping them with X-rays.
Unit 731 would also vivisect individuals without anaesthesia and keep them trapped in pressure chambers until their eyeballs burst.
There was even weapons testing, where subjects would be tied to posts while being shot at from various distances for target pratice.
They would also be on the receiving end of brutal stabbings from knives and bayonets.
It's estimated between 200,000 to 300,000 people by Unit 731 from 1936 it was shut down at the end of the war.
In April 2023, an abandoned bunker used for their monstrous experiments was unearthed.
The World War II "horror bunker" was discovered near the city of Anda in northeast China and is thought to be Unit 731's largest test site.
Archaeologists stumbled across the grisly find in the Heilongjiang province where it has lay unearthed for nearly eight decades.
