Unit 731: Japan's biological force

Wang Xuan is leading the Chinese villagers in their fight for justice

Unit 731 was a special division of the Japanese Army, a scientific and military elite. It had a huge budget specially authorised by the Emperor, to develop weapons of mass destruction that would win the war for Japan. America and Germany had their nuclear arms race. Japan put its faith in germs. Anita McNaught reports.

The Second World War

It was October 1940. Wu was a boy of 11, when his nine-year-old brother fell sick from a mysterious disease, an epidemic that was raging through his village. Terrified that the family would be evicted, Wu's parents kept his brother's sickness a secret from their neighbours.

Wu Shi-Gen pays respects outside the room in which his brother was kept

And fearing the boy would infect his siblings, they locked him in a storeroom at the far end of the house.

His brother had the bubonic plague.

The Japanese war planes which had passed over Wu Shi-Gen's village in Quzhou, southern China several days earlier puzzled its inhabitants. The bombs the planes dropped did not explode, but fell harmlessly to earth, cracking open like eggs. From them poured a bizarre mixture of rice, wheat and fleas. The fleas hopped away, into the dark corners of people's houses.

It was not until several days later, when many villagers were struck down by sickness, that some of the more astute began to make a connection.

White-coated Japanese medics claiming to be from a government epidemic-prevention unit would arrive at villages unannounced, saying they were there to implement hygiene measures, or administer vaccinations. Except that after they left, the village would fall sick.

Even more sinister, were the rare eyewitness, scarcely believed at the time, who told of how Japanese soldiers would take hold of victims, cutting them open while still alive and taking samples, before disposing of the bodies.

But none of these horrors came anywhere close to what was happening in the top secret facilities scattered right through Manchuria in Japanese-occupied Northern China.

Unit 731

Unit 731 was the world's largest and most comprehensive biological warfare programme. Inside Unit 731 the Japanese conducted research and human experimentation on a scale unlike any in the history of humankind.

The exterior remains of Unit 731 facilities

More than 10,000 Chinese, Korean and Russian POWs were slaughtered in these experimental facilities. They were used as human laboratory rats, to research, breed and refine biological weapons.

They were treated as sub-human, and live vivisections were common. The products of the research were tested on Chinese civilians. It is estimated that biological weapons killed more than 300,000 between 1938-1945.

Cover up

As the war came to an end, the Japanese surrendered and the US moved in to run the country's affairs, the officers and scientists responsible were never brought to trial.

The research notes from Unit 731 have been locked away in US military archives

The US military got wind of what the Japanese had been working on and immediately grasped two points: They would never be able to conduct that type of human experimentation at home. And that the research had to be kept from the Russians at all costs.

So the US cut the Japanese officers a deal: Immunity from prosecution for war crimes in return for experimental data.

Taking action

When neither the Japanese government nor the US seemed prepared to admit to either the crimes or the cover-up, a small group of appalled Japanese reached out to the Chinese, and formed an unusual alliance. They were determined to use the system to change the system, and decided a lawsuit was the best way.

They needed to hear the villagers' stories - without living witnesses to the slaughter, they would have no case. Their planned visit to Chong Shan made headlines in both countries.

Wang Xuan has made it her life's work to call the Japanese Government to account

Wang Xuan knew the war stories from the villagers of Chong Shan, in her teens she had been sent there to learn from the peasants. Her province too had been plague-bombed. Her uncle had died of diseases. She realised some form of redress for what her relatives had suffered was possible.

She remembers the day in August 1995 she, working in Japan, read about plans for the law suit in the Japan Times. "I was very excited. I got in touch with the group and I said: I am the offspring from Chong Shan village. I have an obligation to help you."

Wang Xuan has played a crucial role in getting the witnesses to trial, and collecting detailed evidence. She has held political rallies and organised conferences and symposiums. She has lobbied and harried government officials on both sides of the China Sea, and forged international links between academics in Asia and the US.

The lawsuit

When research for the lawsuit began, Wang heard Wu had a story to tell. But Wu, like many of his generation was instinctively humble. He could not see how an old man like himself, with little education and no experience in public affairs could possibly be any help. Wang talked him around.

Wu Shi-Gen keeps his pledge to avenge his family

A group of 180 Chinese villagers including Wu Shi-Gen gave evidence against the Japanese government. Their demands are simple. They want the government first to admit to the extent of the biological warfare waged against the Chinese, and then to apologise and make a compensatory payment. "Sorry is not enough", says Wang Xuan, "the Japanese are a very polite people - they say sorry all the time in their daily lives."

Despite his initial anxieties, for Wu Shi-Gen, the process of confronting his past has been entirely positive. After the deaths of his brother and sister, his father was bayoneted to death by a Japanese soldier. His mother on her deathbed asked her surviving son to avenge the family. Sixty years on, Wu feels he has finally honoured that pledge.

"I feel like a stone has been lifted from my heart", he says.

The verdict is expected in early March.

Now, the Chinese villagers are looking to sue the US government.

Unit 731: Sunday 3 February 2002 at 1915 on BBC Two

Reporter: Anita McNaught
Producer: Giselle Portenier
Deputy Editor: Farah Durrani
Editor: Fiona Murch